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Chesnut RM, Carney N, Maynard H, et al. Rehabilitation for Traumatic Brain Injury. Rockville (MD): Agency for Health Care Policy and Research (US); 1999 Feb. (Evidence Reports/Technology Assessments, No. 2.)
This publication is provided for historical reference only and the information may be out of date.
The results are presented in five sections, one for each of the questions listed in Appendix 1. When necessary, we provide additional information about background and methodology before the discussion of results for each section.
Question 1: Should interdisciplinary rehabilitation begin during the acute hospitalization for traumatic brain injury?
It is widely accepted that patients with severe head injury should undergo a course of inpatient rehabilitation immediately after discharge from the acute care hospital. A retrospective study demonstrated that patients admitted to rehabilitation units less than 35 days after injury required less rehabilitation to achieve the same functional level as those admitted more than 35 days after injury (Cope and Hall, 1982). This study raised the question of whether interdisciplinary rehabilitation should be started earlier than was customary.
Early neurological rehabilitation means starting rehabilitation of brain damaged patients as soon as possible during the acute phase of the trauma or illness, often while the patient is still unconscious. The components of early rehabilitation might include a multidisciplinary family conference and a baseline assessment by a physiatrist, occupational therapist, physical therapist, and when the patient is conscious or has a tracheotomy, a speech therapist (Sherburne, 1986).
Figure 4 shows a causal pathway linking early rehabilitation to potential benefits. Direct comparisons of early rehabilitation with usual care in randomized trials (represented by arcs 1, 2, and 3) would provide the strongest evidence about costs and effectiveness. Because such evidence is not available, the effects of early rehabilitation on costs and outcome must be inferred from indirect, observational studies of each causal link. In general, the opportunities for bias and confounding make it hazardous to make inferences about effectiveness from observational studies (High, Boake, and Lehmkuhl, 1995).
The remaining arcs represent indirect evidence. On the left of the figure, the first link in the causal chain is that early rehabilitation might reduce the total length of stay for the acute admission and rehabilitation combined (arc 4). The next link is that a shorter length of stay would reduce the total costs of care (arc 7). On the right, the first link is that patients who undergo early rehabilitation will be discharged to the inpatient rehabilitation service in better condition than those who receive usual care (arc 5). The next link is that, as a result, scores on functional assessment instruments at the end of rehabilitation will be the same or better as in usual care, despite the shorter length of stay (arc 6). An implicit assumption, indicated by arc 8 in the figure, is that better scores on these assessments translates into better health outcomes after discharge from the rehabilitation unit.
Although such evidence cannot ever be as strong as evidence from a well-conducted experimental trial, certain methods of study design or analysis can improve the reliability of the findings. First, the baseline characteristics of the patients in the compared groups should be described in detail using reliable measures of severity, comorbidity, and other information that might be associated with the outcome of interest. At a minimum, these measures are age, GCS scores, and indicators of severity and mechanism of injury, multiple injuries, and preinjury function. Second, matching, stratification, or statistical adjustment for these risk factors should be used to minimize the influence of confounders on the study's observed results. We used these study characteristics as inclusion criteria to identify high-quality studies of the relations depicted in the causal pathway. Third, the study must report at least one relevant outcome measure, such as:
- Presence or absence of complications.
- Length of stay in the hospital.
- Costs of immediate care and long-term financial burden.
- Health status at discharge from the acute care hospital.
- Long-term measure of impairment.
- Long-term measure of disability.
Of the 87 articles that passed the eligibility screen and were assigned to Questions 1 and 2, 14 were potentially relevant to the timing of intensive rehabilitation. Of these, two were review articles (Cope, 1995; Jorgensen, 1997), three were studies that contained no original data (Johnson and Roethig-Johnson, 1989; Kock and Fuhrmann, 1992; Kosubek, Feldmann, and Schwendemann, 1996), and one was a case report (Sherburne, 1986). The eight remaining articles are discussed below.
Direct Evidence
There is no direct evidence from randomized trials about the effect of early neurological rehabilitation on health outcomes.
Indirect Evidence
Comparative studies
No prospective, randomized controlled trials of the effects of early rehabilitation on length of stay, condition at the time of entry into a rehabilitation unit, or long-term costs have been done. Moreover, no nonrandomized (observational) controlled study fully met the criteria described above.
Mackay and colleagues (Mackay, Bernstein, Chapman, et al., 1992) conducted the premier study of integrating formal rehabilitation into the acute-care setting. Although the study has serious limitations, it is the only study to compare groups of patients that clearly received different rehabilitation interventions during the acute phase of TBI (see Evidence Table 1). The authors looked retrospectively at 38 severely injured patients (GCS 3-8 on admission at the trauma center) consecutively discharged from inpatient rehabilitation between 1984 and 1990. These patients had been transferred from 11 different acute care hospitals. Nonformalized acute rehabilitation was performed at 10 hospitals. Acute, formalized early rehabilitation was performed at a single hospital. Formalized trauma rehabilitation was described as: ...evaluation and treatment on admission to the acute hospital by a physiatrist, physical therapist, occupational therapist, and speech and language pathologist. This intervention, which continued throughout the acute admission, involved structured multisensory stimulation, orientation, exercise, and positioning to decrease posturing and help prevent contractures and sensory deprivation. Goal-oriented treatment was provided by using a variety of early intervention approaches from both a rehabilitative and preventive framework (Mackay, Bernstein, Chapman, et al., p. 637).
This program was initiated very early at the formalized rehabilitation hospital, uniformly beginning while patients were in coma an average of 2 days after admission. At the 10 nonformalized acute rehabilitation hospitals, therapy was started during coma in 42 percent of patients, an average of 23 days after admission. For the nonformalized group, 14 percent received only physical therapy, 65 percent did not receive speech therapy, and 14 percent did not receive any rehabilitation.
Severity of injury was rated using GCS score, injury severity score (ISS), RLA score, pupillary and pain responses, CT scans, associated injuries, and surgical interventions. The main outcome variables were LOS at the trauma and rehabilitation hospitals and condition on discharge from the rehabilitation unit (length of coma, RLA at discharge from acute care and rehabilitation).
The authors found that the patients in the formalized treatment group had coma durations and rehabilitation stays about one-third the length of patients in the nonformalized group. There was no difference in acute hospital LOS. The acute LOS ranged from 50 to 60 days. The rehabilitation LOS was 106 days for the formal system and 239 days for the nonformal system, giving rather long total mean LOS of 158 days and 303 days, respectively. Physical/motor, sensory/perceptual, and cognitive/language outcomes were better for the formalized group. These were scored using a specified but nonstandardized rating system. The differences in length of coma, rehabilitation LOS, total LOS, and RLA at discharge from the acute hospital remained large and statistically significant after statistical adjustment for the initial GCS and RLA scores.
Is it plausible that providing comprehensive rehabilitation during coma could reduce the average length of coma by 35 days? The patients in the compared groups were similar in age, associated injuries and initial GCS, ISS, and RLA scores. However, other predictors of a long length of stay in rehabilitation, such as more detailed head CT findings (Cowen, Meythaler, DeVivo, et al., 1995), extremity fracture, and FIM scores (High, Hall, Rosenthal, et al., 1996), were not recorded. As others have pointed out (High, Boake, and Lehmkuhl, 1995), the sample consisted of 38 patients recruited over 6 years, and it is not clear whether they were representative of patients with severe head trauma generally.
A major weakness of the paper is that the results are reported only as means for the compared groups, making it impossible to determine how many patients in the formal early rehabilitation benefitted. Because of the small sample size, it is possible that the very large difference in length of stay reflects the influence of one or more outliers in the group who did not receive formal early rehabilitation. Moreover, no information is provided about the reasons for the longer LOS in this group, so the mechanism by which early rehabilitation might have affected rehabilitation LOS is not clear.
Does earlier transfer to a rehabilitation unit affect rehabilitation LOS (arc 4)?
A number of studies have examined whether early initiation of rehabilitation during the acute hospitalization for TBI is associated with a shorter rehabilitation LOS. The evidence presented in these studies is indirect because early transfer to a rehabilitation unit is not the same, or even necessarily similar, to initiating rehabilitation in the days immediately following postinjury stabilization.
As mentioned earlier, Cope and Hall (1982) retrospectively analyzed the influence of early rehabilitation on hospital LOS and costs. They arbitrarily defined the threshold dividing early and late rehabilitation as 35 days based on the median interval between injury and admission for their overall patient group. They matched two groups of patients (16 early and 20 late patients) for length of coma and analyzed other variables between groups including age, acute GCS (assigned retrospectively), DRS and GOS at entry to rehabilitation, evoked potentials, continence, social status, and physiological impairment (rated on an unspecified set of tests). None of these differences were statistically significant by t-statistics, but the researchers did not use multivariate analysis.
Acute hospitalization days, acute-rehabilitation days, and total hospital days were all greater in number, reaching statistical significance, in the delayed-rehabilitation group. Total hospital stay was over twice as long. Of interest, when the researchers looked at outcome measures at the time of discharge, both the DRS and the GOS appeared similar, suggesting that the patients reached a comparable level of recovery at the time of discharge.
As the authors noted, the most important limitation of this study is that the ability to match the compared groups is very limited. It seems likely that rehabilitation was started earlier in some patients because they were doing better to begin with. In addition, as in the Mackay, Bernstein, Chapman, et al. (1992) study, only mean LOS was reported, so it is possible that a few outliers were responsible for the large differences observed. In general, most patients who have a shorter acute hospital LOS go home, while those who have a longer LOS are more likely to enter a rehabilitation unit (Andersen, Sharkey, Schwartz, et al., 1992). This raises a question of a potential bias (the "Will Rogers phenomenon") that, among patients who have similar admission GCS scores, those who are discharged early are likely to be healthier than those who are not.
Five studies have used multivariate analysis methods to identify factors associated with a long rehabilitation LOS (Andersen, Sharkey, Schwartz, et al., 1992; Cowen, Meythaler, DeVivo, et al., 1995; High, Hall, Rosenthal, et al., 1996; Rappaport, Herrero-Backe, Rappaport, et al., 1989; Spettell, Ellis, Ross, et al., 1991). Four of these studies found an association between early initiation of rehabilitation and a shorter rehabilitation LOS. In one study of 59 patients with severe injuries from a single rehabilitation facility, sex, GCS motor score, and acute LOS provided the best prediction of rehabilitation LOS, accounting for 34 percent of the total variance in a stepwise regression model (Spettell, Ellis, Ross, et al., 1991). After controlling for acute LOS, duration of coma was no longer an independent predictor of rehabilitation LOS. A study of 91 patients admitted to a single university inpatient rehabilitation center had similar findings (Cowen, Meythaler, DeVivo, et al., 1995). In that study--which included patients with mild, moderate, and severe injuries--admission FIM motor score and the length of the acute hospitalization were the strongest predictors of rehabilitation LOS.
A larger, prospective study of 525 patients in the TBI Model Systems sample confirmed some of these findings. The study by High, Hall, Rosenthal, et al. (1996) examined the association between initial severity of TBI, rehabilitation admission FIM, neurologic and extracranial medical complications, mechanism of injury, and payer source in predicting hospital LOS and charges. Patients' initial presentations ranged from mild to extremely severe and were generally skewed toward the severe end of the scale. Patients with lower GCS scores reached rehabilitation later, stayed longer, and generated higher charges than less severely injured patients. For patients within a given TBI severity, rehabilitation LOS and costs increased as acute hospitalization LOS and rehabilitation admission FIM increased. The effect of the admission FIM score was a very powerful predictor of rehabilitation LOS. For example, patients who had a GCS of 8 or less and an average FIM score 2.5 had an average rehabilitation LOS of 70 days, while patients who had a GCS of 8 or less and an average FIM score 4.5 had an average LOS of 21 days. In a regression analysis, acute care LOS was an independent predictor of rehabilitation LOS, along with GCS, average admission FIM, duration of coma, and medical complications. Together, these variables explained 50 percent of the variance in rehabilitation LOS. However, because the portion of explanatory power attributable to acute care LOS was not reported, it is not clear how strongly these results support the view that acute care LOS is a major determinant of rehabilitation LOS.
In this study (High, Hall, Rosenthal, et al., 1996), age did not correlate with rehabilitation LOS and was not included in the regression models. However, another study performed in the same group of patients found that older patients had much longer rehabilitation LOS than younger patients (89 days versus 55 days), even though acute LOS was not significantly different in the two groups (Cifu, Kreutzer, Marwitz, et al., 1996). These observations suggest that the relation between acute LOS, admission functional status, GCS scores, age, and other factors are complex. As a result, the relation between acute LOS and rehabilitation LOS may apply only within certain subgroups of patients. As mentioned earlier, the complexity of these relationships makes it difficult to interpret the results of Mackay and colleagues' (Mackay, Bernstein, Chapman, et al., 1992) observational comparative study. For example, inclusion of only a few severely injured, older patients with a low admission average FIM could substantially skew the results in one of the compared groups.
Does early rehabilitation reduce total costs (arc 7)?
No studies have examined the relationship between acute hospital LOS and the long-term costs of rehabilitation. In two of the studies discussed above (Cowen, Meythaler, DeVivo, et al., 1995; High, Hall, Rosenthal, et al., 1996), longer acute care LOS was associated with higher inpatient rehabilitation charges, but these studies did not examine direct costs or costs of care after discharge from the rehabilitation unit.
Does early intervention affect outcome (arcs 5 and 6)?
Only a few studies have examined the association between acute hospital LOS and short- or long-term outcomes of rehabilitation. Two of the studies discussed above addressed whether an acute hospital LOS predicts short- or long-term outcomes of rehabilitation. In one study, after adjustment for other risk factors, a longer acute hospital length of stay was mildly associated with a lower GOS score within 11 months of injury (Spettell, Ellis, Ross, et al., 1991). This association was statistically significant, but it was too small to be considered clinically important. In the other study (Cowen, Meythaler, DeVivo, et al., 1995), a longer acute hospitalization was associated with lower FIM motor and cognitive scores at the time of admission to rehabilitation. A longer acute hospitalization and a lower admission FIM motor score were also associated with lower discharge FIM scores.
Does early rehabilitation improve decisionmaking about transfer to a rehabilitation facility?
Hospital bed days in the acute trauma hospital are frequently used by patients waiting for transfer to an appropriate rehabilitation or chronic care facility (Andersen, Sharkey, Schwartz, et al., 1992). Apart from its effect on LOS and condition on admission or discharge from a rehabilitation unit, early involvement of a physiatrist as part of the acute-care trauma team might have other benefits. In theory, early involvement by a physiatrist could improve the process of initiating and supervising the application of rehabilitation techniques as the indications arise for such interventions. As mentioned earlier, in a large, regional, retrospective study, patients seen by a physiatrist in the acute-care setting were much more likely to be provided postacute rehabilitation than patients whose discharge planning team did not include a physiatrist (Wrigley, Yoels, Webb, et al., 1994). While it is not known whether this influence has a positive effect on outcome, it does suggest that formalized early neurological rehabilitation in the acute care setting might have the benefit of optimizing rehabilitative care after discharge.
Conclusions for Question 1
One small, retrospective, observational study from a single rehabilitation facility supports an association between the acute institution of formalized, multidisciplinary, physiatrist-driven TBI rehabilitation and decreased length of stay (acute hospital and acute rehabilitation) and some measures of short-term physiologic (noncognitive) patient outcomes (MacKay, Bernstein, Chapman, et al., 1992). The level of evidence is Class III. This study concerned patients with severe brain injury (GCS 3-8); there is no evidence from comparative studies for or against early rehabilitation in patients with mild or moderate injury.
Some indirect evidence also confirms that early rehabilitation is associated with a shorter inpatient rehabilitation LOS, but this association rests on important assumptions that have not been examined in prospective studies. Most important, the association of acute LOS with rehabilitation LOS and greater rehabilitation costs does not directly imply that shortening acute LOS will result in favorable changes in these outcomes. A common confounding variable in the studies reviewed in this section is the inability to control for the possible correlation between the velocity of recovery and the acute hospital LOS. Patients with TBI who have similar GCS scores on admission may recover at markedly different rates. If a patient evidencing rapid recovery reaches threshold for rehabilitation admission and continues to recover quickly thereafter, his or her acute rehabilitation LOS and total LOS days will be fewer than someone who reaches the same landmark at a slower rate. Because present indicators of TBI severity do not measure rate of recovery, this oversight might explain why the relation between acute LOS and rehabilitation LOS persists even after statistical control for severity of illness on admission.
Another finding in the studies reviewed in this section is that rehabilitation admission FIM and acute care LOS are strongly associated with rehabilitation LOS and outcome. This finding suggests that acute hospitalization LOS is not simply a proxy for injury severity or level of recovery on transfer to rehabilitation.
Future Research on Question 1
In essence, this question addresses the efficacy of starting formal rehabilitation efforts very early during the acute-care stay at the trauma center as opposed to "filling in" until the patient is transferred to a rehabilitation program. Certain therapeutic modalities such as physical therapy are generally felt to be properly started soon after admission because of the known rapidity with which complications such as contractures begin. Although the details of the proper techniques, timing, and intensity of such treatment remain to be determined, it is unlikely that a control group of patients that would receive no acute physical therapy could be ethically formed. Although the indications for early application of other rehabilitation-oriented therapeutic modalities are less clear, similar ethical constraints will likely prevent the development of pure control groups for any specific discipline.
The ability to study the efficacy of a formalized program, however, is not subject to such constraints at the present time. The concept of the acute initiation of formal rehabilitation should be defined as an attempt to begin rehabilitation independently of the patient's location or other extraneous constraints such as medical complications, bed availability, and so forth. Such a formalized system is an attempt to "blur the line" between the stay at the trauma center and the time at a rehabilitation center. It would attempt to divorce the treatment from the milieu so that the patient's needs would drive the treatment.
As such, the integration of such a formalized program into an acute care center's operating procedures could be effected in a prospectively randomized fashion without ethical constraints. Since such rehabilitation efforts properly come under the aegis of a physiatrist, the primary independent variable would be the involvement of a physiatrist overseeing explicit formalized application of rehabilitation techniques to the "experimental" group as compared with continuation of the status quo in the "control group." The dependent variables would be acute care and rehabilitation LOS, outcome at time of discharge from acute care (admission to inpatient rehabilitation), outcome at discharge from rehabilitation, and cost-effectiveness of resource utilization.
For such an investigation to work, patients would have to be classified into working categories at a very early stage so that formalized and standardized rehabilitation protocols designed to meet their needs could be applied. If every patient were to be treated differently, it would not be possible to control for the resulting confounding of treatment variables with the independent variable. On the other hand, since different patients need a different array of therapeutic modalities (differing in terms of treatments, timing, and intensity), managing all patients in the same fashion would not be proper. Therefore, if the research is to be useful, such issues must be addressed prior to onset of the investigation.
It also would be necessary to strictly define the applied therapies, since these would be confounding variables in the analysis. Issues such as timing, intensity, modalities, therapist training, milieu, and so forth would have to be standardized within and between treatment groups. This will be especially critical if multiple centers are to be included in the study and combined in the data analysis.
Such a study would not address which modalities should be applied at what point during the acute care stage. These are separate questions addressing the efficacy of rehabilitation modalities in general. The suggested investigation would, however, address the present, seemingly artificial dependence of the initiation of formal rehabilitation on extraneous variables which commonly occur during the early postinjury period.
Question 2: Does the intensity of inpatient interdisciplinary rehabilitation affect long-term outcomes?
After discharge from an acute care hospital, many people with TBI are admitted to an inpatient facility for intense multidisciplinary rehabilitation. It is widely acknowledged that the evidence supporting the effectiveness of inpatient rehabilitation is weak. A recent review identified eight studies published between 1984 and 1994 on the benefits of inpatient rehabilitation immediately or soon after discharge from an acute care facility (not including studies of "early" rehabilitation discussed in the preceding section) (Hall and Cope, 1995). Of the eight studies, three had control groups (Aronow, 1987; Hall, Mann, High, et al., 1996; Morgan, 1988). Only one study (Aronow, 1987) used a control group that did not undergo inpatient rehabilitation. Two studies (Blackerby, 1990; McLaughlin and Peters, 1993) compared patients who underwent inpatient rehabilitation with those who underwent inpatient rehabilitation plus an additional intervention. Of the four uncontrolled studies (Blackerby, 1990; Heinemann, Sahgal, Cichowski, et al., 1990; McLaughlin and Peters, 1993; Spivack, Spettell, Ellis, et al., 1992), two (Heinemann, Sahgal, Cichowski, et al., 1990; McLaughlin and Peters, 1993) compared measures of patients' function before and after rehabilitation, and two (Blackerby, 1990; Spivack, Spettell, Ellis, et al., 1992) examined the relationship between the intensity of rehabilitation services and outcomes.
A large number of older uncontrolled case series demonstrate that patients who participate in a comprehensive, multidisciplinary rehabilitation program after TBI improve on a variety of measures, including independence in ADLs (Cope and Hall, 1982), language skills (Basso, Capitano, and Vignolo, 1979; David, Enderby, and Bainton, 1982; Lomas and Kertesz, 1978; Sarno, 1976), vocational functioning (Dresser, Meirowsky, Weiss, et al., 1973), and neuropsychological functioning and emotional adjustment (Pazzaglia, Frank, Frank, et al., 1975). The methodologic limitations of these studies have been reviewed elsewhere (High, Boake, Lehmkuhl, et al., 1995).
Do these observational studies provide sufficient evidence that inpatient rehabilitation is an effective intervention? Because they are uncontrolled, these studies cannot prove that the improvements observed would not have occurred anyway in the natural course of recovery from injury. Older series of untreated survivors of TBI strongly suggest that avoidable complications occur frequently among candidates for rehabilitation who are not admitted to an inpatient rehabilitation unit following discharge from an acute care hospital. A study performed in 1969, for example, followed 102 people with TBI whose average length of coma was 3 weeks and whose entry into rehabilitation was delayed an average of 20 months postinjury (Rusk, Block, and Lowman, 1969). These individuals exhibited 30 frozen shoulders, 40 major decubitus ulcers, and approximately 200 other major joint deformities. Rehabilitation efforts in these patients produced significant reversals of these deficits. As the authors argued, however, it is likely that these complications could have been prevented by appropriate admission to a rehabilitation unit following discharge from the hospital.
While it is widely accepted that "doing nothing" is neither a reasonable nor ethical option, many questions remain about the effectiveness and cost of inpatient rehabilitation. How does inpatient rehabilitation compare with modern alternatives, such as outpatient rehabilitation or rehabilitation in a skilled nursing facility? Which components of multidisciplinary rehabilitation are actually responsible for the observed effects? What are the characteristics of the patients who have better results with the application of intensive, interdisciplinary rehabilitation? Does the intensity of rehabilitation services affect long-term outcomes? When should a course of inpatient rehabilitation end?
Challenges in Assessing the Effectiveness of Inpatient Rehabilitation
A precise knowledge of the natural, untreated prognosis of brain injury could reduce uncertainty about the effectiveness of inpatient rehabilitation, but such knowledge is lacking. Because experimental trials of inpatient rehabilitation are unlikely to be performed, investigators have relied on statistical methods to adjust for differences in the baseline characteristics between the groups of patients compared in studies. These groups might be patients who received different intensities of rehabilitation services, received rehabilitation services relatively early or late, or did not receive rehabilitation in the usual course of care. The validity of these methods depends in large part on the predictive ability of the risk factors measured in these studies.
As discussed below, the likelihood of a good outcome depends on many patient characteristics. For this reason, it is impossible to interpret studies that fail to describe the baseline characteristics of the sample under study. In such studies, it is not clear whether the results were due to the interventions under study or to unreported selection factors. Two extremes characterize these studies with respect to the description of populations and samples. On one hand, it is common to have a sample described as "patients who were considered ready for (the intervention) by their occupational therapists" or "consecutive referrals to a vocational rehabilitation program who were considered employable under the right circumstances." On the other hand, the inclusion criteria for the sample may be a lengthy list of narrow parameters, including scores falling within a specific range on a series of neuropsychological tests. In one case, there may be no description of the patients. In the other, the description may be so specific that the results do not apply to the greater proportion of patients.
The nature of rehabilitation makes it difficult to evaluate its effectiveness. Multidisciplinary rehabilitation is a complex intervention. Even in studies that provide evidence that patients undergoing rehabilitation improved, it usually is not possible to determine which specific components of rehabilitation are effective. In general, little description of the precise components of multidisciplinary rehabilitation programs is available. Some studies use the number of hours of performance of individual treatment modalities (e.g., physical therapy, occupational therapy, speech therapy, etc.) as a measure of the intensity of rehabilitation. However, additional hours of specific treatments may be provided to patients who enter rehabilitation with more severe deficits. In addition, their control for the confounding variables that they collected would have been considerably strengthened by the use of multivariate statistical methods such as regression analysis. Even without this confounding, an aggregate measure like time spent with the patient cannot capture the social factors and relationships that can be important components of the therapeutic process.
At present there is no reliable method to measure the effect of exposure to the milieu of the rehabilitation program--the interactions between patients and other patients, nurses, therapists, and physiatrists during the course of an inpatient TBI rehabilitation stay--or to separate their effects from the content of the actual therapy provided. Such information may be critical when attempting to determine whether an inpatient rehabilitation unit or a skilled nursing facility may be interchangeable for a given patient.
Most studies do not provide even descriptive information about the components of rehabilitation and the content of specific interventions. In these studies, rehabilitation is somewhat of a black box--it is defined, by default, as whatever happens between admission to and discharge from a rehabilitation unit. The lack of detail about what constitutes rehabilitation reduces the generalizability of each study's findings and makes it difficult to compare the results of different studies attempting to assess the effectiveness of rehabilitation.
In formulating a strategy for reviewing the literature, we focused on whether information was available to examine the actual mechanisms by which inpatient TBI rehabilitation affects outcomes. Specifically, we sought to examine whether the results of rehabilitation vary according to (1) whether the intervention was directed and managed by a physiatrist and (2) the number, kinds, and frequency of methods applied. Secondarily, we sought to examine which factors predict a good outcome and how these factors may be used in decisions about how and when patients might benefit from inpatient rehabilitation.
The population for this question consists of people who sustained TBI between the ages of 18 and 65 years whose injury severity warranted a trip to a hospital emergency department, transfer to acute care, and subsequent transfer to inpatient rehabilitation. We also intended to focus predominantly on studies that included or measured the following patient characteristics:
- Age.
- Glasgow Coma Scale score.
- Severity of injury.
- Multiple injuries.
- Premorbid data.
- Mechanism of injury (kind of trauma).
- Intracranial diagnosis.
- Functional status.
Finally, studies had to report one or more of the following outcome measures:
- Length of stay in a rehabilitation facility.
- Immediate care costs and long-term financial burden.
- Health status at discharge from inpatient rehabilitation.
- Long-term measure of impairment.
- Long-term measure of disability.
- Independence, relationships, family life, satisfaction.
Of the 87 papers included for review of questions 1 and 2 (see Figure 3), 57 had some relevance to question 2. Of these, 10 primarily addressed predictors of outcome, 22 were uncontrolled followup studies of inpatient rehabilitation, and 20 examined the usefulness or validity of various measures of outcomes. Five studies, which were controlled or quasiexperimental studies that addressed the effectiveness or intensity of inpatient rehabilitation, are discussed in detail in the following sections.
How effective is acute inpatient TBI rehabilitation in general?
Before addressing whether the intensity of inpatient TBI rehabilitation is associated with improved outcome, we examined the more general question of the effectiveness of TBI rehabilitation itself. A large number of uncontrolled case series show that people with brain injuries generally improve by the time of discharge from the acute inpatient rehabilitation facility (Ashley, Persel, and Krych, 1993; Basso, Capitani, and Vignolo, 1979; Ben-Yishay, Silver, Piasetsky, et al., 1987; Cope, Cole, Hall, et al., 1991; Cope and Hall, 1982; David, Enderby, and Bainton, 1982; Dresser, Meirwosky, Weiss, et al., 1973; Eames and Wood, 1985; Evans and Ruff, 1992; Johnston, 1991; Jones and Evans, 1992; Lomas and Kertesz, 1978; Malec, Smigielski, DePompolo, et al., 1993; 1Mills, Nesbeda, Katz, et al., 1992; Panikoff, 1983; Pazzaglia, Frank, Frank, et al., 1975; Prigatano, Fordyce, Zeiner, et al., 1984; Sarno, 1976; Scherzer, 1986; Tuel, Presty, Meythaler, et al., 1992). Because of imperfect knowledge about the natural history of TBI and the nearly complete absence of data about the results of alternative methods of rehabilitation after discharge from the acute care hospital, these Class III studies provide only weak evidence that inpatient rehabilitation is effective. Comparing these studies and aggregating their results into a systematic examination of results was not possible because data were too incomplete to discern the relationship between types of populations or interventions and outcomes.
One quasiexperimental study used an unmatched control group to assess the effectiveness of acute inpatient TBI rehabilitation (Aronow, 1987). Sixty-eight patients were selected from 107 consecutively discharged patients treated at a single inpatient brain injury rehabilitation center. Their long-term outcomes were compared with those of 61 patients selected from 1,400 cases consecutively entered into an epidemiologic database of TBI inpatients at a neurosurgical unit in an area of the country with no comprehensive rehabilitation available for severe TBI. These two groups were termed "rehabilitation" and "nonrehabilitation," respectively. The selection criteria were TBI (> 1 hour of unconsciousness and > 24 hours of altered consciousness), age at injury between 5 and 80, acute hospital LOS > 15 days, and not comatose at the time of acute hospital discharge.
Measures of TBI severity in the Aronow (1987) study were PTA, acute hospital LOS, presence or absence of open brain injury, and number of skull fractures. Age, sex, race, and years postinjury were measured as confounding variables. TBI severity and the other potentially confounding variables were controlled for by using regression analysis, entering the confounding factors into the model prior to adding the rehabilitation versus no rehabilitation variable. The outcome measure was a 13-variable measure that included vocational status; living arrangement; number of recent inpatient treatment episodes; number of recent outpatient episodes; hours of daytime care required; functional status in self-care, mobility, and residential skills; number of home and outside social contacts; and number of physical, cognitive, and emotional symptoms. This standardized outcome measurement was developed unique to this study and has not been otherwise tested. Outcome data were obtained via telephone interview with the person with TBI or a caregiver/relative during a set study period not indexed to time after injury or rehabilitation. Chi square analysis was used to examine differences in PTA between groups, and linear multiple regression modeling was used to control for confounding variables in determining the relationship between rehabilitation and outcome.
At baseline, the rehabilitation and nonrehabilitation groups differed significantly in PTA, the major index of TBI severity used in the study (Aronow, 1987). Seventy percent of the rehabilitation group had PTAs > 4 months, while 74 percent of the nonrehabilitation group had PTAs 1 month. The nonrehabilitation group also was less impaired in self-care activities and memory.
In a multiple regression model adjusting for age, sex, race, injury severity (PTA, acute hospital LOS, open brain injury, number of skull fractures), and years postinjury, rehabilitation was associated with a better long-term outcome (Aronow, 1987). The overall R2 value was 0.551, suggesting that about one-half of the variance in this group was accounted for by the nine predictors plus rehabilitation. Days in acute hospital, duration of posttraumatic amnesia, age at onset, sex, and whether rehabilitation was performed were statistically significant predictors of outcome. However, the correlation coefficient (Pearson r) for rehabilitation was only 0.159, suggesting that only about 3 percent of the variance was related to whether or not rehabilitation was done.
This study (Aronow, 1987) mildly supports the hypothesis that acute inpatient TBI rehabilitation improves outcome. The finding of a benefit despite worse initial severity in the rehabilitation group lends some credence to the results. The study has important weaknesses that have been enumerated by others (High, Boake, and Lehmkuhl, 1995). The obvious baseline differences between the two groups means that the attempt to identify a suitably comparable control population failed. While the statistical analysis was well done, this method of control works best when there is good reason to believe that the two groups being compared are similar. The differences also reflect the underlying problem that the subset of patients admitted to a rehabilitation unit are not representative of the population thought to benefit from it.
Because this was a retrospective study (Aronow, 1987), the authors were limited to information that had been recorded in the patients' charts or (in the case of the control group) data recorded in an epidemiologic study, although all records were abstracted using the same protocol and all followup interviews were conducted using an identical instrument and process. Data on the timing of followup (how long after injury, acute hospital discharge, and rehabilitation discharge the outcome data were collected) were not available. GCS data also were unavailable. Finally, the use of a proprietary outcome instrument prevents comparison of their data to other studies.
Is the intensity of acute inpatient TBI rehabilitation services related to outcome?
There are no prospective randomized controlled trials of different levels of intensity of acute rehabilitation. Four observational studies, three of which are retrospective, addressed the relationship between the intensity of rehabilitation services and outcomes for people with brain injury not due to stroke (Aronow, 1987; Blackerby, 1990; Heinemann, Hamilton, Linacre, et al., 1995; Spivack, Spettell, Ellis, et al., 1992) (see Evidence Table 2).
A retrospective multicenter study of 140 patients admitted between 1990 and 1991 to one of eight rehabilitation hospitals was the best of these studies (Heinemann, Hamilton, Linacre, et al., 1995). Although the study was retrospective, all of the participating hospitals were prospectively collecting data using the Uniform Data Set for Medical Rehabilitation (Granger, Hamilton, and Sherwin, 1986). Intensity of therapy was defined either by the number of billed hours of individual therapeutic modalities (physical therapy, occupational therapy, speech and language services, and psychological services) or by all services combined. The authors examined whether a higher level of services was associated with better motor and cognitive FIM scores, achievement of motor or cognitive potential ([D/C FIM-admit FIM]/[100-admit FIM]), and efficiency of change ([D/C FIM-admit FIM]) at the time of discharge.
An analysis of the interrelationships between intensity and severity of injury or other descriptors revealed that they were not independent. Intensity of treatment covaried with functional status at admission, patient demographics, and medical characteristics. This suggests that the functional status on admission is actually related to the therapy intensity the patient receives. It appears that the patients received more therapy if they were admitted with less cognitive function, had uninterrupted stays, had a longer delay to admission, were younger, and so forth.
Investigation of the relationship between intensity of therapy and their (Heinemann, Hamilton, Linacre, et al., 1995) various outcome measures (discharge motor and cognitive FIM scores, achievement of motor or cognitive potential, and efficiency of change) did not reveal any significant relationship for occupational, physical, or speech therapy intensities. There was also no significant intensity:outcome relationship for intensity of all therapies combined. Only the number of hours of psychologic work per day, usually delivered as cognitive therapy, were associated with any alterations in outcome. These alterations were improvements in discharge cognitive, FIM score, achieved potential gains in cognitive FIM score, and efficiency of cognitive recovery.
The major weaknesses of this paper (Heinemann, Hamilton, Linacre, et al., 1995) are the absence of a specific definition of TBI and lack of control for severity of injury as a confounding, predictive variable. It is unlikely that the admission FIM will cover all of the variance otherwise subsumed by GCS, PTA, and/or duration of unconsciousness (coma). There was no control over or description of differences in treatment between the involved hospitals. Also, the use of billing hours as the index of therapeutic intensity probably included time not spent directly in patient care. Finally, the authors only used one outcome measure (FIM), and there is no long-term followup. Despite these weaknesses, however, the use of prospective data collection and credible analytic techniques make this the most important paper to address the issue of the relationship between intensity of therapy and outcome. It is the only Class II study in this category.
A retrospective study (Spivack, Spettel, Ellis, et al., 1992) examined the influence on outcome measured at rehabilitation discharge of therapeutic intensity during the first treatment month and over the entire stay on 95 patients with TBI. The cohort consisted of patients with a complete set of records who had been admitted to a single inpatient rehabilitation unit between 1988 and 1990. A definition of TBI was not given. It was noted that not all patients were comatose on admission. LOS ranged from 20 to 412 days with a median of 58 days.
Intensity of treatment was calculated as hours of actual treatment performance measured in 15-minute intervals for PT, OT, ST, cognitive remediation, vocational services, neurophysiology, respiratory therapy, therapeutic recreation, and medical services. Intensity of treatment during the first month was the total hours of treatment during that month. Subjects were separated into high- and low-intensity groups based on the median split of treatment hours during the first month. The median was 76 hours with a range of 18 to 196 hours. Average daily intensity of treatment over the entire stay was calculated, and subjects were again classified into high- and low-intensity groups based on the median split. The median was 4 hours per day with a range of 1.4-12.25 hours. The authors (Spivack, Spettel, Ellis, et al., 1992) felt that the true time spent per weekday was probably about one-third higher, since these estimates did not take account of days when therapy could not be administered (passes, holidays, weekends, etc.).
GCS was measured within 24 hours of admission to the trauma hospital. Head AIS score, duration of coma, severity of extracranial injuries (highest non-head AIS), and time since TBI were also measured. The statistical method used to control for these confounding variables was unclear.
The independent variables were intensity of treatment during the first month of rehabilitation, average daily intensity of treatment over the entire LOS, and LOS. All of these independent variables were made binary using the median split method as described above.
The dependent variables were outcome measures. RLA scores were measured on admission and discharge. In addition, therapy-specific outcomes on admission and at discharge were assessed using a seven-point functional status scale developed by clinicians within each rehabilitation discipline. A principal components analysis was used with a varimax rotation conducted on the matrix of correlations among functional scale scores at admission to group the scores on various axes. This resulted in grouping along axes of physical performance, higher-level cognitive skills, and cognitively mediated physical skills. In addition, patients were rated on their RLA scores on admission and discharge.
The statistical methods for assessing the relationships between the independent and dependent variables were analyses of variance and covariance controlling for multiple comparisons.
Analysis of covariants (ANCOVA) with repeated measures analysis was used to investigate treatment intensity and LOS on the dependent variables of admission and discharge scores on physical performance, higher level cognitive skills, cognitively mediated physical skills, and RLA level. In this analysis, LOS and intensity of treatment during the first month of rehabilitation and LOS and average daily intensity of treatment over the entire LOS were separately analyzed.
LOS significantly influenced outcome across all outcome groups. With respect to either intensity of treatment during the first month of rehabilitation or average daily intensity of treatment over the entire LOS, the only statistically significant relationship was between discharge RLA and 1-month treatment intensity. Spivak, Spettel, Ellis, and colleagues (1992) found a borderline nonsignificant relationship (p=0.06) between higher level cognitive skills and average daily treatment intensity. They also found a borderline nonsignificant relationship (p=0.07) for the triple interaction of RLA, LOS, and average daily treatment intensity. Based on this borderline relationship, the authors performed univariate ANOVA analysis on this interaction. This revealed a significant effect of high-intensity treatment during the entire stay on RLA scores on patients with longer stays. This relationship did not hold for patients with short lengths of stay. ANOVA analyses of age and LOS as confounding variables suggested that these variables could not explain the correlation.
There are a number of weaknesses in the paper by Spivak, Spettel, Ellis, and colleagues (1992). Because a precise definition of TBI was not provided, it is difficult to determine the parent population. Additionally, the focus of the analyses was on outcome measures that were derived in the unit and were, therefore, of unestablished validity and reliability. The major weaknesses in this study, however, are the use of the median split method to dichotomize the independent variables and the lack of powerful multivariate statistical methods.
In this case, the median split method is a dichotomizing method of convenience and does not necessarily reflect any underlying physiologic basis. The distribution of intensity times may be influenced by confounding influences of various origins, including brain and extracranial injury characteristics, patient personality, payer characteristics, and so forth. One method to force independent variables into binary distributions would be to determine split thresholds recursively in terms of their influence on outcome. Alternatively, intensity of treatment could have been analyzed during the first month of rehabilitation and average daily intensity of treatment over the entire LOS as continuous variables. The use of the median split method in dividing independent variables might have increased the likelihood of a type II error.
The other major weakness in the paper by Spivak, Spettel, Ellis, and colleagues (1992) is the lack of powerful, multivariate control for confounding variables. As was demonstrated (Heinemann, Hamilton, Linacre, et al., 1995), it is not proper to assume independence between intensity of therapy and severity of injury or other patient descriptors. The analysis would have been considerably strengthened by using regression-type analysis.
In the analysis of results, several inferences were made from the nonsignificant but borderline interactions between higher level cognitive skills and average daily treatment intensity (p=0.06) and the triple interaction of RLA, LOS, and average daily treatment intensity (p=0.07). Based on the latter borderline relationship, a significant effect was found of intensity of treatment during the entire stay on RLA scores on patients with long LOSs. Based on this interaction, suggestions were made on managing the intensity of treatment for patients with more severe injuries. However, the original interaction that inspired these suggestions was not significant (p=.07); consequently, the value of the suggestions is not substantial.
In one retrospective study (Blackerby, 1990), the influence on brain injury outcome of a change in mean daily therapeutic intensity that accompanied a major programmatic change at the study institution was investigated. The study took place at two commercial inpatient head injury rehabilitation provider units run by Rebound, Inc., a commercial provider of head injury rehabilitation services. The charts of all 149 patients with brain injury in the program between 1986 and 1988 were evaluated; 97 percent of the patients were admitted with a diagnosis of TBI. There was no description of TBI provided. Patients were either in a coma treatment program or an acute treatment program. For the prechange group, 55 percent were in the coma treatment program (54 of 98 patients), whereas only 27 percent of patients in the postchange group were in the coma treatment program (14 of 51 patients).
There was no precise measure of TBI severity. Confounding variables quoted in this study included age, level of function on admission, and length of time postinjury as measured on admission. The measure of function on admission was not specified. It was reported that the two groups did not differ with respect to these variables, although the method of handling them as confounding variables is not stated and the raw data are not provided.
The independent variable was intensity of therapy measured as mean number of daily therapy hours for all types of therapy combined. The two groups were formed in 1986 when the rehabilitation provider units altered the structure of their rehabilitation service delivery system. At this time, the intensity of inpatient rehabilitation was increased from an average of 5.5 hours per day to an average of 8 hours per day.
The dependent variable was inpatient rehabilitation LOS. The relationship between the independent and dependent variables was analyzed using t statistics, separately analyzing the coma treatment and acute treatment groups.
The results demonstrated a large change in average length of stay in both the coma and acute treatment programs following the programmatic changes. The variability in the LOS also decreased after the programmatic change. The only statistical examination was a t-test between pre- and postchange LOS for both the coma treatment program and the acute treatment program. Both of these changes were statistically significant as tested.
The differences between these groups in terms of cost was evaluated. The average daily cost for the rehabilitation programs was $785 per day with $350 representing the fixed costs. For the patients in the coma treatment program, the average savings would be $16,950 per patient. For the patients in the acute treatment program, the average savings would be $18,504. It was noted that such cost savings, as well as the decreased variability in LOS that appeared to accompany the change in mean daily therapeutic intensity, would be of use to insurance carriers in predicting and controlling costs.
There are a number of weaknesses in the paper by Blackerby (1990). A strict definition of TBI was not provided, making it difficult to determine the parent population. In addition, there was a lack of control for severity of TBI or other confounding variables. No data on these variables were provided.
The major weakness, however, was the lack of statistical controls for a number of potentially significant confounding variables that are intrinsic to this experimental design. It appears there were major changes in this rehabilitation delivery system that accompanied the increase in mean daily therapy intensity. The paradigm change was described as a change to a "naturalistic activity, total therapeutic day model" that apparently involved adaptations of those activities of interest to the individual before head injury. It was suggested that implementation of internal case management was part of the new system and that "senior clinical staff were added to the programs in the roles of clinical consultants and case managers, which increased staff experience and personnel." The occurrence of programmatic changes of such magnitude will, almost by definition, alter patient management in ways outside of those resulting from the increase in mean daily therapy intensity. If all of these changes could be described and quantified, their confounding influences could be addressed using multivariate statistics. In the absence of these data and such statistical analyses, it is difficult to interpret the results of this report.
Conclusions for Question 2
Based on the current literature, there appears to be little evidence that therapeutic intensity, measured as hours of treatment, is related to the beneficial effects of acute, inpatient TBI rehabilitation when the analysis controls for confounding variables. The only Class II study (Heinemann, Hamilton, Linacre, et al., 1995) found no correlation between intensity of individual or grouped therapeutic interventions and outcome. The second study found statistically significant correlations only for discharge RLA and 1-month treatment intensity (Spivack, Spettell, Ellis, et al., 1992). Nonsignificant trends were reported toward associations between higher level cognitive skills and average daily treatment intensity and for a triple interaction of RLA, LOS, and average daily treatment intensity, but the interpretation of these trends is unclear in the absence of statistical significance or other supporting evidence. The third report (Blackerby, 1990) appears to have been so highly confounded by uncontrolled variables as to render questionable any comparative interpretation of findings.
There are a number of possible reasons why various intensities of rehabilitation do not appear to correlate with functional improvements. First, the effect of specific comorbidities was underinvestigated in these papers. Second, there is a lack of long-term followup in all three studies. Third, these studies did not examine the quality of treatments or the reasons the various therapies were applied.
Another potential explanation for the demonstrated lack of correlation between therapeutic intensity and outcome is that all patients were receiving enough therapy and that added hours did not make a difference. Similarly, the ranges of intensities of treatment (lack of treatment variability) may have been too limited to show differential effect. As Heinemann, Hamilton, Linacre, and others (1995) noted, the Health Care Financing Administration (HCFA) mandated 3 hours per day of therapy for each patient starting in 1983. The legislation may have decreased practice variation that, prior to the regulations, might have been wide enough to affect patient outcomes. Future studies should either consider suspending such constraints or including the influence of such mandated decreases in variation in therapeutic effort into the power calculations used to determine the minimal size of their patient populations.
Overall, however, it also is debatable whether hours of applied therapy is the proper index for therapeutic intensity. The impact of individual therapeutic disciplines may not be independent or even separable, and the time spent in each might not be the best index of their intensity.
The use of hours of applied therapy as the index for therapeutic intensity also raises the question of how to measure the "milieu effect" of comprehensive rehabilitation. The potential contributions to recovery that might arise from formal and/or informal patient-patient, patient-nurse, patient-therapist, and patient-TBI rehabilitation environments have not been addressed in any study to date. Particularly in units devoted to TBI, such a milieu effect should be taken into account in attempting to determine the mechanism of efficacy of the present rehabilitation efforts. This is particularly relevant to such questions as whether delivery of rehabilitation services to a similar group in a setting outside of a formal inpatient rehabilitation unit (i.e., a less expensive setting) is an equally efficacious and, therefore, acceptable alternative method of care delivery.
Future Research on Question 2
Future research into the question of intensity of inpatient rehabilitation must deal specifically with the limitations highlighted in the present body of literature. These deal specifically with the way the question has been asked and generally with the details of describing the patient population and the therapies applied.
The present unidimensional definition of intensity as hours of application appears to be neither an appropriate definition of intensity nor an adequate descriptor of the therapies. In order to examine the importance of hours of application, there must be a description of and control for the other aspects that make up each therapy. These include modalities used, therapist training, interactions between therapeutic disciplines, and so forth, as well as the milieu in which the therapies are delivered. For instance, it is questionable if it is valid to compare two separate physical therapy sessions solely in terms of time spent without addressing what is done within those sessions, who performs the therapies, which aspects of other treatment modalities (for example, cognitive therapy) might be imbedded, etc. Such confounding variables either need to be standardized (preferable) or described in a fashion amenable to subsequent statistical control.
It also is necessary to better describe the patient population being treated. It is highly unlikely that all people with TBI will receive optimal benefit from the same general therapeutic approach. It is critical that the types and magnitudes of impairments resulting from the TBI be described for the patient population, including both the severity of injury and the resultant degrees of physical and cognitive dysfunction. If adequate descriptions are provided, it will be possible to determine the interaction of the various facets of the individual treatment modalities with the types of impairment demonstrated by the people being studied. In addition, it will facilitate subsequent focused studies addressing matching treatment protocols to patient subtypes.
If treatments can be standardized and the patient population can be adequately described, it is possible that RCTs could be performed addressing hours of therapy as the independent variable and outcome as the dependent variable. With the proper standardization, the influence of general milieu also could be addressed by adding it as a second independent variable. Such investigations, if performed in fashions that are replicable and comparable between studies, should prove extremely valuable in furthering our understanding of optimizing types and intensities of treatments for people with specific, defined levels of TBI-induced impairments.
Question 3: Does the application of compensatory cognitive rehabilitation enhance outcomes for people who sustain TBI?
TBI-induced cognitive dysfunction manifests in a spectrum of changes in memory, language, concentration, physical problems, and various behavioral disorders. Several longitudinal studies serve to characterize the nature and extent of cognitive problems following TBI. In a study of United States servicemen discharged for medical and behavioral TBI sequelae (n = 2,243 of total discharge population of 1,879,724), 80 percent were discharged with mild dysfunction, 8 percent with moderate TBI, and 12 percent with severe TBI on the Abbreviated Injury Score for head injury (Ommaya, Dannenberg, Ommaya, et al., 1996). Servicemen who had mild TBI were 1.8 times as likely as other servicemen to be discharged because of behavioral problems. They also were 2.6 times as likely to be discharged for drug and alcohol problems and 2.7 times as likely to be discharged for criminal activities compared with other servicemen. The relative risks of discharge for medical reasons ranged from 7.5 for servicemen with mild TBI to 40.4 for servicemen with server TBI. Longitudinal studies in Sweden (Schalen and Nordstrom, 1994) and Scotland (Brooks, McKinley, Symington, et al., 1987) found outcomes in TBI victims at 5 and 8 years and 7 years postinjury, respectively, that included persistent neurophysical pathology, language disorders, dependence on relatives, and myriad mental or behavioral problems, such as hostility, childish behavior, anger, distraction, and fatigue.
Seeking a theoretical foundation for development of effective interventions, scientists and clinicians have generated a number of models of cognition. These models differ by discipline but generally include the concept that cognition operates as an integrated system consisting of performance fields and various functions within these fields (Goldstein, 1995). The fields include attention, memory and learning, thinking or mental organization, affect and expression, and executive functions. Brain injury will affect overall performance and, depending on the nature and severity of the injury, may have differential effects on performance within these fields. Various strategies are used to help improve damaged intellectual, perceptual, psychomotor, and behavioral skills (Wehman, West, Fry, et al., 1989). These systems of interventions are designed to increase daily functional abilities by improving or augmenting deficits in processing and interpreting information (Coelho, DeRuyter, and Stein, 1996).
One general distinction that serves to classify therapeutic strategies is that between restorative and compensatory cognitive rehabilitation. Restorative cognitive rehabilitation (RCR) is based on the theory that repetitive exercise can restore lost functions (Coelho, DeRuyter, and Stein, 1996). RCR targets internal cognitive processes, with the goal of generalizing improvements to real-world environments. Techniques used in RCR include auditory, visual, and verbal stimulation and practice, number manipulation, computer-assisted stimulation and practice, performance feedback, reinforcement, video feedback, and meta-cognitive procedures such as behavior modification. Refinements in RCR methods involve extensive clinical evaluation to identify specific cognitive processes which are damaged and individual remediation protocols targeting those processes (Sohlberg and Mateer, 1989).
Compensatory cognitive rehabilitation (CCR) strives to develop external, prosthetic assistance for dysfunctions (Wehman, Kreutzer, Sale, et al., 1989). It does not rely on the ability to generalize learning or the restoration of lost abilities. CCR uses visual cues, written instructions, memory notebooks, watches, beepers, computers, or other electronic devices to trigger behavior. Therapists assist by simplifying complex tasks, capturing the patient's attention, reducing distractions, and teaching self-monitoring procedures. CCR also includes jingles, mnemonics, verbal rehearsal, and paraphrasing. The concept of CCR has been expanded to include modification of the behavior of family members, teachers, and other support people present in the life of a person with TBI (Ylvisaker and Feeney, 1996). The adapted behavior of communication partners combines with the technical assistance of prosthetic devices and external cues to provide an environment of supported cognition.
RCR and CCR are not mutually exclusive and are commonly mixed in therapeutic programs for TBI. Restorative training is often enhanced by cues, mnemonics, and other compensatory prosthetics. In the absence of evidence for the differential effectiveness of these interventions, clinicians are compelled to combine and provide protocols according to their experience.
Some insurance programs do not pay for cognitive therapy as a stand-alone treatment or as a clearly defined component of a treatment protocol. Therefore, RCR and CCR techniques may be components of a rehabilitation program that is more traditionally defined and thus eligible for payer reimbursement. For example, many inpatient and TBI day treatment programs use speech and language pathology treatment principles to provide cognitive remediation within a broad and more widely accepted program context of occupational therapy, physical therapy, speech therapy, community integration, and vocational rehabilitation. As a consequence, it is difficult to distinguish the effect of the cognitive strategy from that of the other interventions being applied.
Experts in cognitive rehabilitation have developed specific measures for many of the functions impaired by brain injury. These measures, frequently used by researchers in published studies, are also used by clinicians to diagnose deficits and make decisions about treatment planning. Many also are used to test whether results in patients are consistent with various theories of cognition.
Table 6 shows tests and scales commonly used in practice and the frequency of their use in studies of cognitive rehabilitation. Although practitioners agree the desired outcome of cognitive rehabilitation is improvement in daily function, many of the commonly used scales are intermediate measures rather than health outcomes. For example, the Paced Auditory Serial Attention Task, or PASAT (Gronwall, 1977) is a test of attention in which subjects are presented with a string of digits and are required to add each number to the one preceding. A cognitive rehabilitation study may identify attention as the primary dysfunction for a patient, apply an intervention designed to improve attention, and use the PASAT as a measure of improvement. The rehabilitation program at Auckland Hospital in New Zealand transitions clients from one phase to another when a specific score on the PASAT (mean time scores < 4 seconds) is achieved (Gronwall, 1996). This example raises important questions about published studies of cognitive rehabilitation. First, is the observed improvement on the PASAT greater than that of natural recovery or of other interventions? Related questions include: Can the improvement on the PASAT be attributed to the specific intervention selected for the study? Or, would general stimulation produce the same effect? Does the evidence justify the need for complex, sometimes expensive therapeutic techniques, or would simpler, less expensive techniques work as well?
Second, in this example, do high scores on the PASAT accurately predict whether the patient's attentional performances will function adequately in the context of work or social situations in which distraction and other demands are present? More generally, do the measures used to assess the effectiveness of cognitive rehabilitation predict improvement in real life function?
The causal pathway we used to address these questions is shown in Figure 5. Arc 1 represents the direct effect of cognitive rehabilitation on health outcomes-outcomes that can be felt or experienced by the patient in daily life. A panel of technical experts identified the relevant health outcomes of cognitive rehabilitation for people with TBI (see Chapter 2, Methods, Topic Assessment and Refinement, earlier in this report). The panel, which included a psychologist, a neuropsychologist, and a cognitive rehabilitation therapist, listed the following outcomes:
- Activities of daily living (ADLs).
- Long-term measure of disability (restriction or, as the result of an impairment, inability to perform an activity in the manner or within the range considered normal for a human being).
- Long-term measure of impairment (loss or abnormality of psychological, physiological, or anatomical structure or function).
- Independence, relationships, family life, satisfaction.
- Long-term financial burden.
In the context of a systematic review, "direct" evidence comes from comparative studies that examine the effects of cognitive rehabilitation on measures of these outcomes. Arc 2 represents the direct effect of cognitive rehabilitation on measures of employment such as return to work and job retention.
"Indirect" evidence refers to a causal chain that relies on intermediate measures. In Figure 5, the first link in this chain is between the intervention and intermediate measures of improvement (Arc 3); this link corresponds to the question, "Does cognitive rehabilitation improve scores on intermediate measures of cognitive function, such as the PASAT, WAIS-R, etc.?" The next links in the causal chain correspond to the question, "Do intermediate measures used to assess the effectiveness of cognitive rehabilitation predict improvement in real life function (Arc 4) and employment (Arc 5)?"
Of the 114 potential references identified by the literature search for inclusion in this section of the report, 53 met the predetermined eligibility criteria (see Table 5). Reference lists of reviewed articles and peers identified 20 additional articles, resulting in a total of 73 full-text articles that were retrieved and read. Of those, 41 were excluded: 3 were review articles, 5 were studies with fewer than 5 subjects, 1 was retrospective, and 25 studies were descriptive. Five studies measured independent or dependent variables outside the scope of this research question, and two studies compared clients who were referred for treatment with those referred for testing. While excluded as evidence about effectiveness, the descriptive and observational data from these research efforts provided a foundation for understanding and interpreting the evidence.
The remaining 32 articles were abstracted and are presented in the following categories:
- 1.
Eleven randomized controlled trials:
Five measuring relevant health outcomes (Evidence Table 3).
Six measuring intermediate outcomes (Evidence Table 5).- 2.
Four comparative studies:
One measuring employment outcomes (Evidence Table 4).
Three measuring intermediate outcomes (Evidence Table 6).- 3.
Eight studies of the relationship between intermediate tests and employment (Evidence Table 7).
- 4.
Nine observational studies:
One measuring relevant health outcomes (Evidence Table 8).
Eight measuring intermediate outcomes.
Direct Evidence
Does cognitive rehabilitation improve health outcomes (Arc 1)?
Five randomized controlled trials (Helffenstein and Wechsler,1982; Neistadt, 1992; Novack, Caldwell, Duke, et al., 1996; Ruff and Niemann, 1990; Schmitter-Edgecombe, Fahy, Whelan, et al., 1995) used measures of relevant health outcomes to compare the effects of specific forms of cognitive rehabilitation to other treatments (see Evidence Table 3). Two studies examined CCR, one examined RCR, and two used a combined program of RCR and CCR. Comparison groups were provided unstructured sessions, computer game sessions, and nontherapeutic attention. In one study (Neistadt, 1992) two specific restorative trainings were provided. Each group was trained in one of the skills and tested for both. Treatment time for four of the studies ranged from 10 to 20 hours; the fifth (Ruff and Niemann, 1990) provided 96 hours of treatment. Followup for one study (Schmitter-Edgecombe, Fahy, Whelan, et al., 1995) occurred at 6 months and for a second study (Helffenstein and Wechsler, 1982) at 1 month for six of the subjects; the other studies did not have followup testing.
As seen in Evidence Table 3, the studies varied in setting, populations, size, client chronicity, and measures of severity of injury. These trials involved 137 clients; 69 received the targeted treatments.
Measures used in these studies that approximated important health outcomes were the Functional Independence Measure (FIM) (Novack, Caldwell, Duke et al., 1996), Observed Everyday Memory Failures (EMFs) (Schmitter-Edgecombe, Fahy, Whelan et al., 1995), the Rabideau Kitchen Evaluation Revised (RKE-R) (Neistadt, 1992), the Katz Adjustment Scale (KAS) (Ruff and Niemann, 1990), and a variety of inventories designed to measure anxiety, communication, and relationships (Helffenstein and Wechsler, 1982). In addition, these studies used neuropsychological test batteries and other intermediate measures of cognitive function to evaluate treatment effect.
In two studies, treatment produced statistically significant effects on relevant outcome measures. In one study (Schmitter-Edgecombe, Fahy, Whelan, et al., 1995), individuals trained in the use of notebooks and equipped with wristwatch alarm cues had fewer EMFs than those who did not have the compensatory devices. However, the effect was not present at 6-month followup. In the second study (Helffenstein and Wechsler, 1982), clients who received compensatory training had better results than those given nontherapeutic attention on one variable from an anxiety scale and three variables from a communication scale, and they had better performance on the Interpersonal Relationship Rating Scale and Independent Observer Report Scale. Six scales were used in this study, and the number of variables per scale, as well as group means, were not provided.
In the other three studies described in Evidence Table 3, the cognitive rehabilitation intervention was not more effective than alternatives. The predominantly negative results of these small, Class I and II(a) trials may be mitigated by three important factors. First, in general both groups in these studies improved from pre- to posttreatment, producing no treatment effect in the statistical analysis. This raises questions about what is operating to cause general improvement, stimulation or spontaneous recovery, or both? In each study the comparison group received equal hours of some form of stimulation, some of which was therapy of an unstructured nature. Second, four of the five studies provided 20 hours or less of treatment time. With the pervasive and life-long cognitive deficits that result from TBI, results from interventions of such limited duration should not be generalized to more sustained interventions. Third, it is unclear whether the patients included in these studies are representative of patients who might undergo cognitive rehabilitation in current practice. Along with the small size of studies and the narrow range of interventions studied, the lack of information about the representativeness of included patients makes it difficult to apply the findings of these studies to cognitive rehabilitation practice generally.
Does cognitive rehabilitation improve employment outcomes (Arc 2)?
Randomized controlled trials
There is no direct evidence from randomized trials of the effect of cognitive rehabilitation on employment.
Comparative studies
One study (Prigatano, Fordyce, Zeiner et al., 1984) compared employment outcomes for clients of an intensive cognitive rehabilitation program (NRP) with those of people who were referred to the program but who did not participate (see Evidence Table 4). The intervention involved RCR and CCR in a coordinated multidisciplinary program. Participants were provided a minimum of 624 hours of treatment, 4 days a week, 6 hours a day, over 6 months. The treatment group consisted of patients who entered NRP between February, 1980 and August, 1982 and stayed in the program at least 6 months. Files for referrals to NRP during the same time period who did not enter the program were retrospectively evaluated to provide control group data. Followup took place approximately 3 months after the last client was discharged; consequently, followup varies from between 3 months to 33 months. Eighteen people received the treatment; 17 were the nonclient referrals. Chronicity for the control group was shorter (13.6 months) than for the treatment group (21.6 months). Severity was not specified.
Participants were evaluated with 13 neuropsychological tests, the Katz Adjustment Scale (KAS) relative scale, and a measure of employment. People who were gainfully employed, either part time or full time, or were actively engaged in a realistic school program were considered employed. There were treatment effects on 3 of the 13 neuropsychological tests. Client attrition resulted in a reduction of participants at the time of followup. Of 18 people in the treatment group, 9 were employed at followup (50 percent). Of 13 people in the control group, 5 were employed (38 percent). The statistical significance of this difference was not reported.
Because of the potential and unknown differences between treatment and control groups, interpretation of these results is difficult. The authors (Prigatano, Fordyce, Zeiner, et al., 1984) did not specify why clients in the control group, although referred to NRP, did not participate. It is possible that the same factor or factors that caused them not to participate in NRP operated to influence their employment outcomes (in either direction). This Class II(b) study does not provide evidence for or against the effect of cognitive rehabilitation on employment. However, it provides limited evidence of the effect of the intervention on some intermediate measures of cognitive function.
Indirect Evidence
Does cognitive rehabilitation improve performance on intermediate measures of cognitive function (Arc 3)?
Randomized controlled trials. Six randomized controlled trials (Kerner and Acker, 1985; Niemann, Ruff, and Baser, 1990; Ruff, Baser, Johnston, et al., 1989; Ryan and Ruff, 1988; Thomas-Stonell, Johnson, Schuller, et al., 1994; Twum and Parente, 1994) used a variety of neuropsychological tests and other intermediate measures to compare the effects of different forms of cognitive rehabilitation with each other and with other forms of therapy and stimulation (see Evidence Table 5). Three studies combined RCR and CCR techniques; the other three used RCR exclusively in the interventions. Duration of treatment ranged from a single training session to a total of 160 hours of intervention. Two studies (Kerner and Acker, 1985; Niemann, Ruff, and Baser, 1990) conducted followup testing at 2 weeks. The other studies did not involve followup of participants. The studies varied in setting, client populations, size, client chronicity, and measures of severity of injury. One hundred eighty-two clients were observed; 106 received the targeted treatments.
A number of individual tests of cognition, such as the PASAT, were used in the six RCTs. In addition, three of the studies also used a full battery of neuropsychological subtests, two of which used the San Diego Neuropsychological Test Battery (SDNTB). Three studies produced treatment effects. Outcomes for one (Thomas-Stonell, Johnson, Schuller, et al., 1994) were a computerized screening module and a neuropsychological battery. No followup testing was conducted. Outcomes for the second study (Twum and Parente, 1994) were number of words and colors recalled immediately after practicing mnemonic techniques with the words and colors. No followup testing was conducted. Outcomes for the third study (Kerner and Acker, 1985) were a Memory Index (MI) task and an Acquisition Recall (AR) task, measured in scaled and standard forms. The treatment group received CACR targeting memory retraining. A control group used computers to create graphics, and a second control group had no intervention. With three groups and two forms of measuring each of the two tests, 12 effects were possible. Treatment effects were produced on 5 of the 12 measures at posttreatment. Improvement by the treatment group was not maintained at 2 week followup; however, the two control groups did not receive a followup test, so group differences in the decline were not measured.
Two of the three studies for which there was no treatment effect (Ruff, Baser, Johnston, et al., 1989; Ryan and Ruff, 1988) compared equal amounts of structured cognitive rehabilitation programs with unstructured activities, providing the greatest number of treatment hours among the RCTs in this review. The third (Niemann, Ruff, and Baser, 1990) compared equal hours (36 total) of attention remediation with memory remediation. For all three studies, clients in both treatment and comparison groups improved from pre- to posttreatment. This result underscores the previous suggestion that more may be learned about treatment effects by comparing intervention with no intervention rather than comparing one form of intervention (i.e., structured) with another form (unstructured) in a design that provides equal amounts of time and stimulation. Also, this result suggests there may be a general effect of stimulation, perhaps interacting with spontaneous recovery, that exceeds the effect of the intervention.
To conclude, there is evidence from three small Class I trials that the restorative technique of practice, both with and without the aid of a computer, operates to improve short-term recall on laboratory tests of memory for people with TBI.
Comparative studies
Three studies with comparison groups to which participants were not randomly assigned used laboratory tests to evaluate the effects of cognitive rehabilitation on cognition (Batchelor, Shores, Marosszeky, et al., 1988; Gray, Robertson, Pentland, et al., 1992; Wood and Fussey, 1987) (see Evidence Table 6). All three used computers (CACR) to enhance the intervention. One (Gray, Robertson, Pentland, et al., 1992) compared the effect of CACR with that of recreational computing; the other three compared CACR with therapy that did not make use of computers. Treatment time ranged from 16 to 20 hours. Two studies (Gray, Robertson, Pentland, et al., 1992; Wood and Fussey, 1987) performed followup testing at 6 months and 20 days, respectively. Samples included both inpatients and outpatients; the populations from which they were drawn varied. These studies involved 95 people; 44 received the targeted interventions.
Measures used to evaluate treatment effect included tests developed by the clinic or research project as well as established neuropsychological tests such as the PASAT, WAIS-R, Taylor Figure, and Digit Symbol. Of 36 intermediate tests performed, 2 of the 3 studies produced treatment effects on 9 tests. Group means were not presented, preventing an assessment of the magnitude of improvement. As with the RCTs for this category, equal amounts of stimulation were provided treatment and control groups. Improvements from posttreatment to followup suggest the presence of spontaneous recovery. These small, Class II(b) studies provide limited evidence that CACR improves performance on laboratory tests of cognition for people with TBI.
Table 6 summarizes the results of the studies, reviewed above, that used laboratory tests of cognition to measure treatment effects. The first column lists all the laboratory-based tests that were used, within categories as defined by Lezak (1995): attention and orientation; memory, verbal, and language; construction; concept formation and reasoning; and executive functions and motor performance. Two additional categories are batteries and global tests, and miscellaneous and clinic-specific tests. Column (a) shows the number of RCTs in which cognitive rehabilitation had a statistically significant effect on the test listed for that row; column (b) presents the same information for comparative studies. Column (c) gives the number of correlational studies in which there was a significant correlation between the test and a health outcome or employment. Columns (d), (e), and (f) list numbers of studies for each test for which there was no effect or association. Column (g) is the proportion of times the test was used in controlled studies (RCTs and other comparative studies) that the intervention produced an effect on the test. Column (h) is the proportion of times the test was used in correlational studies that there was a positive correlation between the test and a health outcome or employment. Ninety-one different laboratory-based tests of cognition were used in 160 distinct evaluations in the studies presented in evidence tables for this research question. For RCTs, the research design most capable of providing evidence for effectiveness, there was an effect of treatment 14 of 51 times (27 percent). Other comparative studies produced a treatment effect 20 of 61 times (33 percent). For correlational studies, there was a significant association between intermediate tests and health outcomes or employment 33 of 64 times (52 percent). Thus, as the strength of evidence decreased, the effect increased. In addition, as the strength of research design decreased, the number of studies increased.
As discussed earlier, although the evidence is limited, there is some suggestion that certain cognitive rehabilitation methods improve performance on neuropsychological tests and other laboratory-based methods of evaluating cognitive function. The next question addresses the second link in the indirect path from intervention to relevant outcome.
Do intermediate measures of cognitive function associate with health outcomes (Arc 4) or employment (Arc 5)?
No studies meeting the criteria for this review reported an association between laboratory-based measures of cognitive function and health outcomes such as functional independence, ADLs, or measures of everyday memory.
Evidence Table 7 presents eight studies that measured the cognitive function of people with TBI using a variety of neuropsychological tests and also measured postinjury employment status or productivity and activity level (Brooks, McKinlay, Symington, et al., 1987; Cicerone, Smith, Ellmo, et al., 1996; Ezrachi, Ben-Yishay, Kay, et al., 1991; Fabiano and Crewe, 1995; Fraser, Dikmen, McLean, et al., 1988; Girard, Brown, Hashimoto, et al., 1996; Ip, Dornan, and Schentag, 1995; Najenson, Grosswasser, Mendelson, et al., 1980). Each used some correlation-based method to analyze the relationship between the laboratory tests and employment status. Although specific research methods varied, in general these studies retrospectively gathered hospital and inpatient rehabilitation chart data to establish test scores and then interviewed clients and/or relatives to establish employment status. Sample sizes ranged from 20 to 152 participants; a total of 724 people were observed. Chronicity and severity varied within and across samples.
In all, 123 tests of cognition were administered. Two studies (Ezrachi, Ben-Yishay, Kay et al., 1991; Girard, Brown, Hashimoto et al., 1996) used numeric scales to measure productivity from 1 (worst) to 10 and 6, respectively. Four studies (Brooks, McKinlay, Symington, et al., 1987; Cicerone, Smith, Ellmo, et al., 1996; Fraser, Dikmen, McLean, et al., 1988; Ip, Dornan, and Schentag, 1995) used dichotomous measures of return to work or former level of productive activity. Two (Fabiano and Crewe, 1995; Najenson, Grosswasser, Mendelson, et al., 1980) placed clients into five and four categories of employment, respectively. Methods of analysis included regression, t-tests, chi-square, Wilcoxon rank sum, discriminant analysis, and factor analysis.
About half of the time, clients with higher intermediate test scores had returned to work or productivity, either full or part time, but not necessarily to the pretrauma level. In one study that used a regression analysis (Girard, Brown, Hashimoto, et al., 1996), 9 of 28 test scores, combined with 3 demographic characteristics, accounted for 30 percent of the variance in outcome; 19 of the tests did not help explain the difference in employment outcomes. In another study (Fabiano and Crewe, 1995) intermediate test scores were used in a discriminant analysis to derive a formula for predicting employment status. With this method, high scores on tests accurately predicted full-time employment 62 percent of the time, and low scores on tests accurately predicted unemployment 67 percent of the time. These proportions indicate that, while there appears to be some relationship between intermediate measures of cognition and employment, the association is not strong.
Observational Research
Although research designs without control groups are limited, they can be a source of hypotheses which could be tested in controlled trial settings. This section highlights insights from studies with uncontrolled research designs identified in our literature search.
Nine observational studies of clients before and after cognitive rehabilitation fulfilled the criteria for inclusion in this review (Cicerone and Giacino, 1992; Deacon and Campbell, 1991; Glisky, Schacter, and Tulving, 1986; Goldstein, McCue, Turner, et al., 1988; Middleton, Lambert, and Seggar, 1991; Ponsford and Kinsella, 1988; Ruff, Mahaffey, Engel, et al., 1994; Scherzer, 1986; Wilson, Evans, Emslie, et al., 1997). One study used a measure of a relevant health outcome, everyday memory failures (EMFs), to evaluate treatment effect, and it is presented in Evidence Table 8 (Wilson, Evans, Emslie, et al., 1997).
The other eight studies either compared clients' performance from baseline phase to treatment phase, provided the same or similar treatments to different matched groups, or combined group and individual methods of measurement. In general, results indicate that for the selected clients treated in these clinical studies, one-on-one interaction with therapists in a rehabilitation environment is likely to improve individual performance on targeted laboratory tasks. Because the studies are not comparative, the improvement observed does not contribute to the body of evidence about the intervention being provided. However, the fact that clients do in fact improve gives rise to innovations in rehabilitation technology that may be useful to people with TBI and thus warrant further evaluation.
For example, in the study presented in Evidence Table 8 (Wilson, Evans, Emslie, et al., 1997) 15 clients were provided an electronic device, programmed to assist them in remembering to do routine daily tasks. Prior to the intervention, they were interviewed to identify targets for memory remediation unique and important to them. Thus the intervention was individually adapted. The score for everyday memory failures (EMFs) was the number of times a target was forgotten. EMFs were measured for 2 to 6 weeks during baseline. During the treatment phase, which lasted 12 weeks, each person in the study wore and used the device. The return-to-baseline phase was 3 weeks.
All participants had significant decreases in EMFs during treatment. During return-to-baseline, EMFs increased for 11 of the 15 participants; five increases were statistically significant. The results of this study suggest that the use of an electronic cueing device decreases EMFs for some people with TBI. These findings also contribute to the evidence for the link represented by Arc 1 of the causal pathway. The observational design of this study weakens its value as evidence of effectiveness. However, in considering that the nature of most of the interventions reviewed here are not individually adapted and on face value do not appear to be as pragmatic as an effective reminder device, this study is useful in that it generates a hypothesis about an intervention that may have the potential to prosthetically improve memory for a person with TBI.
Conclusions for Question 3
Very few controlled studies of cognitive rehabilitation have examined health outcomes or employment. Two small randomized controlled trials (Class I) and one observational study provide evidence of the direct effect of compensatory cognitive devices (notebooks, wristwatch alarms, programmed reminder devices) on the reduction of EMFs for people with TBI. A second randomized controlled trial provides evidence that compensatory cognitive rehabilitation reduces anxiety and improves self-concept and interpersonal relationships for people with TBI.
In the absence of strong and sufficient evidence for a direct effect of cognitive interventions on health and employment, we examined a causal pathway linking cognitive rehabilitation to intermediate measures of cognition and subsequent associations between those measures and health or employment. Two small randomized controlled trials (Class I) provide limited evidence that practice and CACR improve performance on laboratory-based measures of immediate recall. However, no studies evaluated the link between cognitive tests and health outcomes, and associations between performance on cognitive tests and posttrauma employment and productivity were inconsistent.
Future Research on Question 3
Identifying and evaluating outcomes that are relevant to people with TBI and their families is the first priority of a research agenda. Among the studies we reviewed, perhaps the most pragmatic outcome measure used was that of everyday memory failures. It is possible that the absence of treatment effect in these studies could be a function of the study's lack of relevance in the lives of the people being evaluated, represented in outcome measures and interventions that have little meaning to those people.
It is also important to identify the laboratory tests that are strongest and most reliable in their ability to measure cognitive function in relevant contexts, and to standardize their use across research projects and hospital and clinical settings.
Two other questions for future research on topics not specifically addressed in this review are: (1) When is the client ready for the intervention? and (2) What are the markers of that readiness? Large, multicenter comparisons may provide initial information for a research design to investigate these questions.
In general, the studies in this review that did not produce a treatment effect compared one form of cognitive rehabilitation with another form, CACR to non-CACR practice, and were specific to unstructured rehabilitation methods. Treatment effects were not observed when one kind of remediation was compared with another when there were equal levels of stimulation for both treatment and comparison groups. What are the differential effects of general stimulation and technology? As TBI rehabilitation technology grows, costs escalate. Consequently, certain subsets of the total population of survivors--those with liberal insurance policies and/or private money--will receive the intervention. It is important for clients as well as payers to know if the new technology leads to improvement or whether the increased level of stimulation used to deliver the technology results in the improvement.
Question 4: Does the application of supported employment enhance outcomes for people with TBI?
The goal of supported employment is to enable people with severe long-term or permanent deficit to resume a productive life through on-site aid and advocacy provided at the place of employment. Programs in supported employment began in the late 1970s as university-based demonstration projects and then became a part of government-sponsored rehabilitation programs. They have been applied to a wide range of populations who were previously considered unemployable, particularly people with mental retardation, but also including people suffering from neural, psychiatric, and physical disabilities (Wehman, Revell, Kregel, et al., 1991). More recently, the techniques have been applied to help survivors of TBI resume a productive life.
Chronic unemployment has both a personal and a social cost. For the person, regular work is an important source of personal satisfaction and social identity (Partridge, 1996). It not only may provide financial resources, but it also forms the basis of self-image and a claim on social recognition and reward (Shepherd, 1981). Work and a sense of vocation can contribute to a personal sense of worth and competence, a sense of belonging and well-being, and to other psychological states essential to mental health (Pettifer, 1993). The fundamental value of work is illustrated by Roe's (1956) suggestion that it is the only social role that can fulfill all the stages of Maslow's (1987) hierarchy of needs, ranging from safety, through esteem, to self-actualization. Chronic unemployment, especially beginning early in life, is an important threat to personal mental health. Survivors of TBI often were injured just as they approached or reached their full potential as workers. The social cost is evident when we consider that more than 60 percent of survivors of TBI are men under 35 years of age (Wehman, West, Fry, et al., 1989). This is precisely the population who tend to be highly skilled workers, at the peak of their powers, with 30 years or more of productive life remaining. That contribution to society is foreclosed by their absence from the work force or by the greatly diminished roles they must play after injury. And it is not only gainful employment that is lost to the person and to society, the loss also includes the whole variety of a person's productive work as a student, homemaker, and other important social contributions which the person might have made (Sander, Kreutzer, Rosenthal, et al., 1996).
Definitions
There are at least five models of supported employment: (1) individual placements, (2) work enclaves, (3) apprenticeships, (4) small businesses, and (5) mobile work crews (Powell, Pancsofar, Steere, et al., 1991). The most common model is individual placement, which provides training and ongoing support individually to each survivor, in settings where fewer than 5 percent of the workers are disabled. The aim is to provide a quality match between worker and job requirements, including high job satisfaction by both worker and employer and decent wages (Ellerd and Moore, 1992). This is the model usually recommended for survivors of TBI (Wehman, Kreutzer, Stonnington, et al., 1988), though a variation of the apprenticeship model has also been tried (Curl, Fraser, Cook, et al., 1996). One of the most detailed definitions of the individual placement model is by Kreutzer, Wehman, Morton, and colleagues (1988). They identify four essential components, all of which must be tuned to the type of deficit of the client (in this case, the client with TBI):
- Job placement. This includes (a) matching job needs to client abilities and potential, (b) facilitating employer and client communications, (c) facilitating caretaker communications, (d) arranging travel arrangements or training, and (e) analyzing the job environment to detect potential problems.
- Job site training and advocacy. This emphasizes the active role of the employment specialist, job coordinator, or job coach, who is often cited as the key professional in supported employment programs (Wehman, West, Fry, et al., 1989; Ellerd and Moore, 1992). The job coach serves functions usually left to the employer in conventional vocational rehabilitation (e.g., training). The job coach also is proactive in identifying problems and designing solutions in cooperation with all the parties involved.
- Ongoing assessment. This involves continuous monitoring of key aspects of the client's work performance. There is an intense intervention by the job coach at the beginning, but this is expected to diminish, or "fade," as the client settles into a successful work adjustment (Ellerd and Moore, 1992; Wehman, Sherron, Kregel, et al., 1993). This process is well illustrated in Figure 1 of the article by Wehman, Kreutzer, West, et al., 1990.
- Job retention and follow-along. A continuing, proactive process in which the job coach tries to anticipate problems and intervene early to prevent crises from disrupting the client's adapted job placement. This assistance to the client is of indefinite duration, although it is expected to diminish over time (Wehman, Sherron, Kregel, et al., 1993).
The hallmark of supported employment methods is that they are applied on the job, in the actual work environment, to help the client succeed. Off-job training and practice to prepare the client for work may be an important prelude to supported employment in some programs, but the job coach always accompanies the client to the job site to work out on-the-spot solutions to problems as they arise and to mediate between employer and client. This problem-solving-in-situ is a defining principle of the method of supported employment (Kreutzer, Wehman, Morton, et al., 1988). Finally, these programs usually aim at competitive employment, usually defined as employment in a setting about 95 percent occupied by workers without disabilities and paying at least the official minimum wage (Wehman, Kreutzer, West, et al., 1990; Ellerd and Moore, 1992). They do not aim at placement in sheltered workshops or other settings designed primarily to accommodate the needs of disabled workers. There is a strong commitment to placing the client in the highest job position possible and to approach or exceed the preinjury level of work.
Supported employment is necessary only in cases where standard vocational rehabilitation is not sufficient to secure the desired level of employment for a survivor of TBI. In this respect, supported employment could be considered an extension of vocational rehabilitation into the actual job site as the final stage of helping a particular survivor resume a productive life. Studies of postinjury employment in which survivors are sorted by severity of injury show that not all survivors of TBI require this extra step. People suffering mild injury (GCS = 13) are usually reemployed at high rates: from about 60 to 85 percent within 1 year postinjury, and this high rate is maintained up to 15 years later (Dikman, Temkin, Machamer, et al., 1994; Schwab, Grafman, Salazar, et al., 1993; Edna and Cappelen, 1987; Fraser, Dikman, McLean, et al., 1988). In those same studies, people suffering from moderate or severe injury do not fare as well. The reemployment rates for moderate injury (GCS = 9 to 12) for the same periods are 50 to 60 percent, and for severe injury (GCS = 8), reemployment ranges from 20 to 30 percent.
The GCS alone may not always be the best predictor of employment success in multivariate analyses including other severity measures (Abrams and Toms Barker, 1991). It seems evident, however, that supported employment is most necessary for severe injury because regular vocational rehabilitation programs are insufficient. Even a variety of other interventions before job placement--such as cognitive training, with and without occupational trials, and behavior modification--show only limited success (Wehman, Kreutzer, West, et al., 1990). In addition, about one-half of survivors with moderate TBI and at least 15 to 20 percent of survivors with mild cases also might benefit from supported employment programs.
Ideally, as an extension of vocational rehabilitation, supported employment would address the problems that lead to lost jobs. Devany and colleagues at the Medical College of Virginia (Devany, Kreutzer, Halberstadt, et al., 1991) found that survivors of TBI who had trouble with reemployment suffered from four kinds of difficulties:
- Somatic problems, like debility, loss of balance, and motor deficiencies.
- Cognitive problems, like loss of memory, inability to focus attention, obsessions, and indecisiveness.
- Behavioral problems, like inertia, restlessness, depression, and impatience.
- Communication and social problems, like contentiousness and various disorders of speech and writing.
They also found that the survivors' scores on the Minnesota Multiphasic Personality Inventory (MMPI) showed peaks on scales 8 (schizophrenia), 4 (psychopathic deviate), and 2 (depression), in that order of magnitude. Valid MMPI scores might be problematic with this population, but the pattern found seems to match the common clinical impression. A configuration of 8-4-2 on the MMPI indicates a depressed person with severe interpersonal and social deficits who could easily alarm or offend others. Add this to the various motor and cognitive deficits already noted, and we have a formidable set of obstacles to placing and maintaining a person with a severe TBI in a job setting. The underlying assumption of the supported employment model is that all people referred to the program are employable under suitable conditions (Wehman, Sherron, Kregel, et al., 1993). Successful programs focus on finding or making those conditions in support of client success at work.
Of the 93 articles retrieved for review, 42 were excluded based on initial exclusion criteria, reducing the total number of articles to 51. Two investigators read all articles retrieved through the database search, as well as five additional articles acquired from reference lists and recommendations from peers, for a total of 56 articles.
Direct Evidence
There is no direct evidence from randomized trials about the efficacy of supported employment.
Indirect Evidence
No Class I or IIa studies of supported employment were found in the literature. In one prospective, controlled, observational study, Haffey and Abrams (1991) measured job placement and retention rates of 130 participants in a program of supported employment, the "Work Reentry Program" or WRP. These results were compared with those of 35 clients in a day-treatment program and 76 individuals who had received no postacute rehabilitation (the "comparison group"). Participants in the WRP program were recontacted every 6 months for up to 3 years. Other subjects were followed for varying amounts of time over 3 years, depending on when they entered the study. A total of 87 (67 percent) of the 130 participants entering the program were placed in employment. Followup for the 87 placements was as follows:
- 1 to 6 months of followup: 18 participants.
- 7 to 12 months of followup: 23 participants.
- 13 to 18 months of followup: 17 participants.
- 19 to 24 months of followup: 15 participants.
- > 24 months of followup: 14 participants.
The second series has been reported in a number of publications (Wehman, West, Fry, et al., 1989; Wehman, Kreutzer, West, et al., 1989; Wehman, Kreutzer, West, et al., 1990; Wehman, Sherron, Kregel, et al., 1993). These studies evaluated the outcomes of supported employment in a prospective registry study. In the first article cited, the sample included five survivors followed for 75 weeks (1.4 years); by the last article in the series the sample had increased to 115 consecutive referrals followed for up to 60 months (5 years). These individuals passed through two consecutive phases of vocational rehabilitation: first, the standard postrehabilitation services, then a supported employment program.
For convenience in the remainder of this report, we will refer to the first study as Haffey and Abrams and to the second series of studies, taken as a group, as the Virginia series, after the home of the researchers in the Medical College of Virginia.
Posttrauma vocational success in the Virginia series was compared with the rates of preinjury employment success of each client, who served as his or her own control in the study. Preinjury employment is thus taken as a baseline control for results in the two subsequent phases of intervention--the last of which was supported employment--as each client passed through the following history: Preinjury employment (baseline) => posttrauma employment (1st phase intervention) => supported employment (2nd phase intervention).
Measures of employment success in the Virginia series were (1) number of jobs held per client, (2) mean hourly wage, (3) mean monthly wage, (4) mean annual wage, (5) monthly employment ratio (MER). The last is an index of vocational success developed by the Virginia group. It is the ratio (with specific definitions of the two variables): number of months client employed/number of months client could have been employed (Wehman, Sherron, Kregel, et al., 1993).
Results were measured over 5 years of operation with measures of outcome taken weekly (Wehman, Kreutzer, West, et al., 1989). During that time, 80 of the 115 entering clients were placed in jobs, but it is not clear how many of the 115 were followed for all 5 years. In the whole series of studies, we have reports on 5 clients in 1989 (Wehman, West, Fry, et al., 1989) and 20 clients later in the same year (Wehman, Kreutzer, West, et al., 1989). In 1990, there is a report of 53 clients (Wehman, Kreutzer, West, et al., 1990) and in 1993 the total is 115 (Wehman, Sherron, Kregel, et al., 1993). From this pattern in the reports, we may infer that about five clients were followed for a full 5 years, 15 clients for between 4 and 5 years, 33 clients for at least 3 years, and 62 for less than 3 years.
Selection and allocation of clients
There was no random selection or allocation to groups in either of the studies reviewed. In the Haffey and Abrams study, assignment to the two treatments and the on "comparison group" was "determined by factors that ordinarily lead to referral to rehabilitation services," according to the authors. (1) Clients in the WRP (supported employment program) were referred by the State rehabilitation department if they had employment potential "under the right circumstances" (which perhaps meant a program like the WRP). Clients believed to have "absolutely no employment potential" by rehabilitation counselors, the clients themselves, or family members were not admitted to the WRP. (2) The second treatment group (the day-treatment program) contained survivors for whom "competitive employment was not a current goal" because of medical problems, personal and family preference, economic disincentives (pension, social security), and other engagements (homemaker, student). (3) The comparison group was made up of consecutive discharges from inpatient TBI rehabilitation who did not elect to attend the WRP because they (a) thought the services unnecessary, (b) believed they were too disabled to work, (c) played a dependent role with caregivers, (d) feared jeopardizing benefits, or (e) were active substance abusers.
In the Virginia series, the sample was 115 consecutive referrals by clients' supervising physiatrists to the supported employment program. All met the following criteria: (1) age between 18 and 64 years, (2) severe TBI: GCS 8 for 6 hours, (3) strong evidence that the person could not work successfully without ongoing job support, like previous postinjury failure, client doubts, or doubts by physician, family, or counselors. No client was excluded simply for having cognitive, physical, or psychosocial deficits. Some of the studies in the series (1990) indicate that clients were also excluded on evidence of active substance abuse.
Models of supported employment tested
Both studies used some variant of the individual placement model of supported employment, but the two versions differed significantly. Both programs had extensive analysis of client characteristics, preferences, abilities, and deficits to guide optimum placement of the clients, the active participation of the job coach at the work site, and continuing but "fading" support for the client on the job. The analyses of client need and capacities and job requirements are extremely detailed in both programs, but Haffey and Abrams appear to use more behavioral criteria (like simulated work samples), and the Virginia group seems to rely more on screening and respondent information (see Wehman, Kreutzer, West, et al., 1989 for the screening form used). However, the program used in Haffey and Abrams had a component of preemployment training available to the clients which was not a feature of the Virginia program. Haffey and Abrams included two preemployment training sessions for the clients: (1) work hardening, using real and simulated work activity to develop "stamina, work competencies, work behaviors, and productivity levels"; and (2) the Transitional Employment Program (TEP), placing the client in a salaried capacity in the hospital dietary or environmental services department with a job coach for 3 to 4 months. These features are in contrast to the Virginia model, which is predicated on the "assumption ... that ... cognitive retraining, work adjustment, work hardening and social skills training, may be best provided at the job site while the person is already employed." This is a fundamental difference in approach which is made explicit by a later statement in the same place: "Supported employment does not promote job readiness training, but instead emphasizes using a person's current abilities and strengths" (Wehman, Sherron, Kregel, et al., 1993).
Outcomes
Outcomes are summarized in the evidence tables. In the Haffey and Abrams study, 68 percent of the WRP clients secured competitive employment, and only 18 percent were considered chronically unemployed. Only 39 percent of the day-treatment group and 34 percent of the comparison group reported any employment after discharge. At the last followup period reported, 71 percent of the WRP clients placed were still working, but no retention rates for the day-treatment and comparison groups were reported. See Table 7 for a summary of the results from the Virginia studies (Wehman, Sherron, Kregel, et al., 1993).
Conclusions for Question 4
There is Class IIb evidence that supported employment can improve the vocational outcomes of TBI survivors. Almost all information about supported employment comes from two bodies of work, each of which use different experimental designs and different models of supported employment. The findings have not been replicated in other settings or by other centers, so the generalizability of these programs remains untested.
In the Virginia studies, the clients all had severe cases of TBI as rated by the GCS. In the Haffey and Abrams experiment, no GCS scores are given, but the data provided on severity of injury show median length of coma in the three groups ranging from 6 to 7 days, with the median value for the entire sample of 199 cases at 7 days and the overall range from 0 to > 30 days. In the 80 job-placed survivors of the Virginia series (Wehman, Sherron, Kregel, et al., 1993), the average length of coma was 48 days, and the range was from 0 to 182 days. Clearly, the Haffey and Abrams sample contained many people with moderate or even mild injuries, while the Virginia sample consisted entirely of people with severe injuries. We have already noted, in the Introduction to this report, that severity of injury has an important effect on vocational success.
There also are difficulties in interpretation that are derived from problems with the individual study designs and with confounded variables and biases in the groups being compared. In both studies, the prospective data collection avoids the hazards of retrospective inference, but the lack of a control condition in the Virginia studies and the highly biased allocation of clients to the groups being compared in the Haffey and Abrams research make it impossible to clearly interpret results. In the Haffey and Abrams study, there are so many differences among the groups being compared that comparisons are almost meaningless. The supported employment group is heavily biased toward better vocational outcomes, containing only clients specially selected by vocational counselors as likely prospects for work. The day-treatment group, however, was filled with clients for whom "competitive employment was not a current goal," and the comparison group was made up of clients who had rejected a chance at supported employment and had multiple motives to avoid work altogether. Then, when the three groups were tested for differences in client characteristics (see Table 1, Haffey and Abrams, 1991), the only difference found was that the comparison group was significantly less likely to have been employed at the time of injury. With a stacked deck, no one is surprised when the dealer wins the hand, and the superior vocational performance of the supported employment group in this experiment is likewise an anticlimax.
The problems with the Virginia series are of another sort. They arise from the inherent limitations of the design itself, since case-control studies without separate control groups and unbiased allocation of participants are unable to untangle confounded variables. Repeated measures on a single group are bound to be confounded with variables for which there are no controls. An observation made by Wehman, Sherron, Kregel, et al. (1993) will illustrate the problem. They note that during the economic recession of 1990 to 1992--the worst in the United States since the 1970s--nearly 20 percent of their program participants lost their jobs due to layoffs. The design of the Virginia studies compares baseline levels of employment preinjury with subsequent performance under two levels of vocational rehabilitation, including supported employment as the final stage.
In the Virginia sample, the average age at injury was 24.8 years, and the average age at referral to the program was 30.9 years, making the average interval from injury to entry in the program 6.1 years. The average time to job placement after program entry is about 1 year more, and the subsequent followup in the series of studies under review ranges up to 5 years, with a substantial proportion of the clients at least 3 years into followup. Simple arithmetic discloses that the average time from preinjury employment to postinjury followup is on the order of 10 to 12 years, and for about half the clients the interval will be even longer. This is the time elapsed between baseline measures of preinjury vocational success and postinjury outcome measures under supported employment. It is a significant possibility that economic changes over a 10- to 12-year period (or more, for half of the sample) would have significant effects on employment. Those economic effects will be confounded with the effects of supported employment programs running at the same time, and there is no way to separate the two kinds of effects unless a control group of clients, without supported employment, is measured over the same interval. Likely, there are many other confounded variables at play in the same way, including unknown ones.
In spite of the problems mentioned, it remains true that all the programs of supported employment reviewed showed better rates of vocational success than the baseline expectations of survivors of TBI who received only standard postacute rehabilitation or even with special kinds of preemployment vocational counseling and training (see "Problems Addressed" section in the Introduction to this report). The success documented by the Virginia series with survivors with severe injuries is especially convincing in this respect. Supported employment appears to be a promising way to increase the vocational success of survivors of TBI, but the present literature does not give definitive proof of its effectiveness and does not provide enough clarity on why it works or guidance to the best applications of the method.
Future Research on Question 4
Experimental designs
The greatest overall need for the evaluation of supported employment programs is a series of trials with adequate controls and unbiased allocation of clients to the conditions compared. The prototype of this kind of evaluation is the randomized, controlled trial (RCT), in which a representative sample from a population of survivors of TBI is randomly assigned to programs in supported employment and to various control conditions, which may include alternate interventions, no interventions, or both. These experiments may be very difficult or impossible to do because of the conditions under which rehabilitation programs operate. There may not be access to representative samples of survivors of TBI, for example, or it may be difficult or impossible to insulate the different experimental conditions from each other when the clients and caregivers from the different groups live in the same community and have informal social exchanges with each other. The same may be true for professional staff. Sometimes ideal experimental conditions must be approximated and sufficient measures taken to allow supplementary regression analyses to clarify confounded variables or covariance analyses to control for unavoidable allocation biases. These are the realities of field research. However, we need better studies than we now have to clarify the effects of supported employment.
Independent variables
In addition to the main independent variables of intervention and control groups, a number of measures of client characteristics may be reconsidered in light of past research. On the matter of injury severity, for example, the general rule holds that clients with moderate to severe TBI injuries (GCS < 10) are most at risk for poor vocational outcomes in unsupported work settings (see Introduction to this review). Stambrook, Peters, Deviaene, et al. (1990) found that admission GCS scores, low preinjury vocational status, older age, and physical and psychological problems were the best discriminators of postinjury success.
The Virginia studies focus entirely on clients with severe injuries (GCS < 8) because that is where most of the problem lies. However, the link between severity of injury and unemployment is not perfect, and a substantial group of survivors with even mild injuries (15 to 40 percent) fail at work. In a study of predictors of vocational success 1 year after injury (Cifu, Keyser-Marcus, Lopez, et al., 1997), the Virginia group found several effective measures, including injury severity (admission GCS, highest GCS, length of coma, and length of PTA); acute measures of physical functioning (admission FIM, admission DRS, discharge DRS); cognitive functioning (logical memory delay); and behavioral functioning (admission RLAS, discharge RLAS, NRS excitement factor). But very long intervals can elapse between injury and reemployment: an average of 5 to 7 years or more is common, with half of clients waiting longer times (Wehman, Sherron, Kregel, et al., 1993; Courtney, 1992; Roessler, Schriner, and Price, 1992). There is a need for finer discrimination among the states of deficit at the time of entry into employment programs than is afforded by GCS scores in the acute phase.
One possibility is to use more proximate assessments of deficit which assess abilities needed in the workplace. If supported employment programs are aimed at clients with greatest risk of vocational failure--as in the Virginia series--postacute measures may be better predictors of postinjury work success. For example, some cognitive deficits (executive function/flexibility), emotional disturbances (aggressiveness, depression), and low ADL ratings appear to be better predictors of employment after TBI than severity of injury (Crepeau and Scherzer, 1993). The research done by the Virginia group on "easy" and "difficult" groups of clients to place and train in employment settings (Wehman, Kregel, Sherron, et al., 1993) may be another basis for better discrimination of client characteristics and better matches between clients and work settings, as is the work done on the kinds of problems leading to job loss in supported employment programs for clients with TBI (Sale, West, Sherron, et al., 1991).
Another class of independent variables might be called cointerventions and concurrent variables. Cointerventions are the unprogrammed interventions made by family, coworkers, employers, and so on that may affect success or failure on the job. These are difficult to identify and measure, but it is unrealistic to assume that the job coach is the only helper or advocate of the client, and these other interventions may have powerful effects on outcome. An example of concurrent variables is the observation (Wehman, Sherron, Kregel, et al., 1993) that, in one instance, 20 percent of clients in a supported employment program lost their jobs to layoffs during an economic recession.
Dependent variables
Also important with regard to outcome variables are length of followup and frequency of measurement of outcomes. Some studies take weekly measures (the Virginia series) and others longer periods, such as every 6 months (Haffey and Abrams, 1991). Generally, frequency of measurement depends on how detailed the knowledge of job adjustment needs to be for effective job coaching. In the early stages, close monitoring is necessary; as the job coach "fades," the measures may be more spaced. More important for assessing the efficacy of supported employment is the length of followup. We recommend that followup be an integrated part of all supported employment programs, as a built-in component, and that it go on indefinitely. The play of variables that determine vocational success may act over long periods of time, and adequate length of followup approximates the entire work career of the client. The example of the Virginia series, which made periodic updates on a cumulating sample, shows the value of this strategy.
Another issue related to outcome is the criterion of vocational success. If a broader criterion is adopted, it would extend the range of the methods of supported employment into those of supported activity. The list of primary areas of activity (Sander, Kreutzer, Rosenthal, et al., 1996), which includes homemaker, student, volunteer, and retired, as well as competitively employed, and specially employed (including supported employment), is one approach to a set of criteria for vocational success which is broader than simply work-for-wages. Another approach is age-appropriate activity, as proposed by Prigatano, Fordyce, Zeiner, et al. (1984), which gives due weight to homemaking and schooling as successful vocations.
Some of the methods designed for supported employment (onsite aid and advocacy, the activity coach) might be extended experimentally to settings in the home and school. The Monthly Employment Ratio (MER), a measure of vocational success developed by the Virginia group (Wehman, Kreutzer, West, et al., 1989), has gained some currency in the field and is worth adopting as a standard outcome measure for supported employment. It could easily be extended into a more general measure, a Monthly Activity Ratio (MAR), based on similar principles of definition, for studies adopting a wider set of criteria of vocational success.
Strategies of evaluation
The main focus of the work reviewed here is what may be called outcome evaluation. This strategy is entirely appropriate in medicine when seeking a basis for treatment in evidence, but there might be some utility to other modes of evaluation as well. Observations of process, participant perspectives on the programs (by clients, staff, employers, family, etc.), and assessment of client empowerment could add entirely new dimensions to our knowledge of how programs work. These approaches to "unpacking the black box" of a supported employment program would aim to show how successful programs produce their effects and why unsuccessful programs fail. This is the kind of detailed information we need to improve the design of interventions. It is likely that much remains to be discovered about how individual differences among clients interact with aspects of the programs serving them. Johnson (1987) found that factors like ability to return to one's previous job, being provided a work trial or easier work, and long periods of support were more important in determining successful reemployment than the client's state of deficit. These are typical benefits provided by supported employment. But what makes for easier work, what is support, and what variations in both answer the needs of particular survivors? Many details remain obscure. In many instances, alternate approaches to evaluation will require qualitative methods in combination with the quantitative measures of job retention and success. Models of these other types of evaluation are available from a wide variety of applications, and there is a developing set of methods for applying them (Chelimski and Shadish, 1997). Some work along the suggested lines is already being done--the studies of client characteristics cited in the discussion of independent variables are examples--but an expanded effort to measure the operating details of the programs might be useful in the design and implementation of new or improved programs.
Models of supported employment
Most of the work found in our search was done on one model of supported employment. The individual placement model is most favored because it is the most flexible and appropriate one for returning individual survivors to their preinjury workplace or to new settings where their particular abilities and deficits allow a successful adjustment. The practical nature of this model of supported employment is its own justification. However, its success has perhaps obscured some good reasons for more work on other models.
Recently, a variant of the apprentice model has trained supervisors and coworkers to act as on-site "job coaches" for workers with TBI (Curl and Chisholm, 1993; Curl, Fraser, Cook, et al., 1996). Even with provision of salary subsidies to the "job coaches," this model offers a potentially effective and relatively low cost method of providing supported employment. Some coworkers refused payment for their services, and the ones paid cost only about 10 percent of the salary of a professional job coach (see Table 2, Curl, Fraser, Cook, et al., 1996). Even if coworkers were paid for as long as the average professional job coach, it would still be much less costly to provide this service. This may be an especially effective model in settings of professional and highly skilled work forces, where the coworker has the knowledge and skill to be the most effective helper.
Another model which may be worth considering is a revised concept of the work enclave as a work setting designed to fit the abilities and deficits of survivors of TBI, perhaps in company of people with complementary deficits, like other physical disabilities, or with family caregivers. Although a departure from the trend toward integration and normalization of TBI survivors at work, this approach may have certain benefits, especially for the most severely disabled. All models of supported employment were first applied to non-TBI populations, and this modified version of a work enclave is proven effective with some of the same populations served by early programs of individual placement, such as people with chronic mental illness (Fairweather, Sanders, Maynard, et al., 1969).
This different version of the work enclave might offer some of the same resources of natural support as other social settings--like community support groups--which enhance and enable the survivor's life: the camaraderie of fellow survivors and the intrinsic interest and help of family and friends. The combination of work and social relations available in this kind of milieu may have some potential to increase both vocational success and quality of life for survivors of TBI in the same setting and the same program. If effective, it could provide a powerful combination of benefits to relieve that part of the burden of illness in TBI which is linked to vocation and work, providing a personal sense of worth and competence, a sense of belonging and well being, and other psychological states essential to mental health (Pettifer, 1993).
Question 5: Does the provision of long-term care coordination enhance the general functional status of people with TBI?
Some long-term functional setbacks and disturbing psychosocial sequelae may not become apparent in survivors of TBI for several years. Some consequences are even preventable, but time is often critical to maximize treatment and forestall secondary effects. One response to issues of how and when to access TBI rehabilitation has been case-management programs designed to monitor survivors and match them with appropriate services. The various impairments that survivors experience often give rise to secondary problems of vocational failure, social isolation, and extended functional dependency that can increase over time at various rates (Brooks, Campsie, Symington, et al., 1986; Goering, Farkas, Lancee, et al., 1988; Kaitaro, Koskinen, and Kaipio, 1995; Olver, Ponsford, and Curran, 1996; Schalen and Nordstrom, 1994; Spatt, Zebenholzer, and Oder, 1997; Van Balen, Mulder, and Keyser, 1996).
TBI impairments present three major survivor- and family-adjustment issues for which case management is a recommended solution. One problem is that survivors may not receive appropriate postacute clinical rehabilitation services, or they may enter programs too early or too late to benefit. There is growing evidence that some effects of TBI can be ameliorated by postacute rehabilitation as late as 10 years postinjury (Hall and Cope, 1995; Johnston and Lewis, 1991; Spatt, Zebenholzer, and Oder, 1997). In spite of this knowledge, survivors and their families may not be entering functional improvement and/or psychosocial support programs at strategic postinjury points. This has been attributed to fragmented responsibility for screening, lack of clarity about how to identify rehabilitation readiness, and lack of accountability among program providers (Greenwood and Brooks, 1994). One reason for the lack of extended rehabilitation could be that programs are either not locally available or are not supported with incoming clients as reported in Europe (McMillan, Morris, Brooks, et al., 1988; Van Balen, Mulder, and Keyser, 1996).
However, other explanations pertain to the nature of the population needs. As the postinjury time increases, the difficulties experienced by survivors of TBI tend to be increasingly subtle and diverse, and informal caregivers fail to recognize and determine their needs. Professionals in primary and specialty care services also can experience confusion about what should be done at which points in the postinjury continuum by which disciplines in which types of service agencies. Unless an advocate is available to maintain interagency relationships and awareness of program improvements and opportunities, it is difficult for survivors of TBI, their families, and their professional caregivers to create a timely recovery agenda and facilitate access.
A second problem for which case management is a projected solution is the relatively low reemployment rate among survivors of TBI. According to Malec, Buffington, Moessner, et al. (1995), the long-term unemployment rate among patients with moderate to severe injuries without vocational intervention is low--about 50 percent--and only one-third resume independent competitive employment. Studies also have shown that the period between brain injury and return to work or initiation of vocational services is long--about 5 to 7 years (Wehman, Sherron, Kregel, et al., 1993; Courtney, 1992; Roessler, Schriner, and Price, 1992).
Without appropriate employment support, survivors may experience additional psychosocial problems because of misinterpretation or lack of understanding about the symptoms. For instance, concentration and memory problems may be perceived as lack of motivation, insensitivity, or mental illness. Most survivors need assistance developing career goals, learning work skills, and seeking and maintaining employment. This is based on evidence of improvement with declining long-term unemployment and underemployment rates being attributed to employment support and work reentry programs for greater numbers of survivors of TBI (Sample and Rowntree, 1995). Because vocational rehabilitation programs that support employment entry or reentry are not a standard feature of TBI clinical rehabilitation programs, case managers or vocational coordinators are considered one means of bridging the agency gap between rehabilitation and reemployment.
A third TBI-related problem for which case management is recommended is the issue of family burden. Studies of head injury effects on family life have shown that cognitive impairments and personality changes are more disruptive than physical disabilities (Cavallo, Kay, and Ezrachi, 1992; Gleckman and Brill, 1995; Godfrey, Knight, and Bishara, 1991; Hendryx, 1989; Kreutzer, Marwitz, and Kepler, 1992; Kwasnica and Heinemann, 1994; Leathem, Heath, and Woolley, 1996; Livingston, 1987), and that parents are better able to withstand such stresses than spouses (Panting and Merry, 1972; Thomsen, 1974). Rosenbaum and Najenson (1976) found that wives of survivors of brain injury experienced more strain and a greater sense of isolation and loneliness than did wives of paraplegics. Others also report evidence of subjective family strain and friction (Brooks, Campsie, Symington, et al, 1986; Weddell, Oddy, and Jenkins, 1980). The burden on families is so widely recognized that programs aimed specifically at support or assistance for the relatives of survivors of TBI are being developed (Carnevale, 1996; Peters, Gluck, and McCormick, 1992; Ragnarsson, Thomas, and Zasler, 1993; Sanguinetti and Catanzaro, 1987). This problem of family difficulty in coping with the effects of TBI merits a broad effort to identify antecedents and effective approaches, including case management.
Definitions
Case management has emerged as a possible solution because it systematically monitors client needs over time and facilitates access to services in various institutions and programs across communities. Case managers usually serve people with long-term or chronic conditions because they have complex needs and find it difficult to navigate the health and/or social care systems.
According to the Commission for Case Manager Certification (1996), case management is: A means for achieving client wellness and autonomy through advocacy, communication, education, identification of service resources and service facilitation while ensuring that available resources are being used in a timely and cost-effective manner in order to obtain optimum value for both the client and the reimbursement source (p. 2).
The role typically includes admission or intake assessment, care-plan development, service referral, coordination of service details, and collaboration with care providers, informal caregivers, and the client (Goering, Farkas, Lancee, et al., 1988; Goodwin, 1994) and may also include authorization of service payments (Ashley, Krych, Persel, et al., 1994; Evans and Watke, 1995). The domain is to determine service needs and to access service elements with a sequence and timing that will result in desired outcomes for the client and family as well as desired outcomes such as cost control for the service organization.
Case Management Characteristics and Desired Outcomes
One characteristic of case management is the adopted mission of the employing organization. Since case managers are found in hospitals, rehabilitation programs, health departments, aging services departments, mental health services, insurance companies, and managed care organizations (Gerber, 1994), the focus can vary from acute-care disposition planning to long-term patient advocacy to service cost control. As the orientation and purpose of case management programs vary, outcomes may reflect the differences. In order for case management interventions to be compared and tested for effectiveness, it is important to define the specific purposes and aspects of case management that are provided.
Case managers also focus on helping clients move across institutional or organizational systems and across provider disciplines. Managing these boundary issues calls for a collaborative approach around a common focus--the client and family. Understanding case management role specifications and the extent of boundary work is also critical for comparing programs and interpreting research that tests case management effects.
Within this context of TBI incidence and long-term effects, problems experienced by clients and their families, and the definition and role of case management, our study was conducted to identify evidence of case management effectiveness. The purpose was to review the literature for controlled clinical studies of the influence of care coordination on targeted outcomes among TBI rehabilitation populations of clients and their families.
Of the 69 articles retrieved for review, 27 were excluded based on the initial exclusion criteria, reducing the total number of articles reviewed to 42. Two investigators read all retrieved articles from the database search, as well as relevant articles found on reference lists of the retrieved articles and those obtained from colleagues, for a total of 73 articles. The only criterion for study selection in this phase was that case management was an independent variable. By mutual agreement three studies were critically analyzed and entered into Tables 1 and 2 to report evidence of case management effectiveness in TBI rehabilitation.
Results
Does the provision of long-term care coordination enhance the general functional status of people with TBI? The search strategies yielded three controlled studies of case management effectiveness in TBI rehabilitation. Two studies compared case management with non-case management, and one study compared two types of case management. Two studies were completed trials (Ashley, Krych, Persel, et al., 1994; Greenwood and Brooks, 1994), and one article (Malec, Buffington, Moessner, et al., 1995) presented preliminary results after 1 year of data collection.
Although all the studies addressed case management effectiveness, they differed in most of the design characteristics, as reported in Table 1. Regarding study purpose, Ashley, Krych, Persel, et al. (1994) focused on the level of independence following rehabilitation, while Greenwood and Brooks (1994) addressed the rehabilitation process, client employment and quality of life, and family burden; and Malec and colleagues (Malec, Buffington, Moessner, et al., 1995) measured employment outcomes. Two designs were group comparisons, and one design compared outcome rates with previously established baseline rates (Malec, Buffington, Moessner, et al., 1995). In the only clinical trial that tested the effects of case management on client outcomes (Greenwood and Brooks, 1994), the intervention was allocated to sequentially admitted clients in randomized sites. In the other two studies, sequential admission for eligible subjects was also the intervention allocation method, but the subjects were at different stages of recovery. The number of subject withdrawals and the number of exclusions were reported in two papers; in the third, the subjects were all clients who met the inclusion criteria and could be matched to the control group. The sample sizes were moderately high (> 100) in two studies (Greenwood and Brooks, 1994; Malec, Buffington, Moessner, et al., 1995), and small (n = 39) in one (Ashley, Krych, Persel, et al., 1994).
Each selected study focused on a different subpopulation. In two studies, the subjects were homogeneous for level of disability: either moderate disability (mean Disability Rating Scale [DRS] scores of 4.95 and 5.17) (Ashley, Krych, Persel, et al., 1994); or severe disability (mean DRS scores of 16.2 and 18.3, and mean Glasgow Coma Scale [GCS] scores of 6.6 and 5.5) (Greenwood and Brooks, 1994). In the third study, the sample at 1 year consisted of clients with mild injuries (79 percent), as rated with the GCS and moderate or severe injuries (21 percent) Malec, Buffington, Moessner, et al., 1995). Comparison group differences made it necessary to control for aspects that may have affected the outcomes, but no controls were mentioned in the preliminary report by Malec, Buffington, Moessner, et al., 1995.
The studies also tested different models of case management intervention. Ashley, Krych, Persel, et al. (1994) evaluated two insurance-coverage models in which the key aspects were the authority to approve disability payment and rehabilitation service claims, although this was not defined, and differences between the two groups for this characteristic were not reported. Also, the report did not include any other behavioral or role descriptors to compare and contrast the two intervention models. In fact, although a key independent variable was same versus different case managers, it is not clear from the description whether all subjects in one group had the same case manager or whether each subject in the group had one case manager for the entire post-TBI period. Greenwood and Brooks (1994) tested a medical model of case management, defined as clinical needs assessment during acute hospital care, formulation of a proactive rehabilitation plan, and facilitation of rehabilitation cooperation and involvement among patients, family, and professionals.
Malec, Buffington, Moessner, et al. (1995) evaluated a medical-plus-vocational model of case management. They defined it as assessment and rehabilitation planning during acute hospital care for the provision of medical outpatient rehabilitation services and for vocational counseling and planning related to employment services available in the community. Although there were presumably common role behaviors in these two models, there were not enough details offered in the Greenwood and Brooks (1994) report to determine whether the case manager referrals had led to subsequent care coordination by vocational counselors and others. If so, the Greenwood model would have been similar to the Malec model. Only one study identified the discipline or training that the case managers had received (Malec, Buffington, Moessner, et al., 1995). Also, the intervention periods varied by study and by client need, which no doubt influenced the results.
In addition, other design aspects differed among the studies. The data collection points ranged from 1 month to 24 months, with only two studies measuring outcomes at 12 months. In two projects, the research spanned 2 years, but subjects were followed for less than 2 years if they had not entered the study at the beginning. Also, due to the team-oriented nature of case management and the close institutional quarters of the subjects, blind assessments of the subjects were not possible. Therefore, care delivered by the case managers and other team members could have differed among groups and influenced the outcomes. Additionally, there was almost no information about possible cointerventions--such as other service providers--who may have offered care coordination and continuity, and there was very limited information about the other types of rehabilitation services that may have influenced client outcomes.
There are very few studies of the effectiveness of case management. The results of these studies are mixed (Evidence Table for case management, 2). There is evidence from Class III studies that case management improved vocational status. This was associated with the single case manager and insurance approach (Ashley, Krych, Persel, et al., 1994), as well as with the combined nurse and vocational case manager model (Malec, Buffington, Moessner, et al., 1995).
There were conflicting results about the effects of case management on disability or functional status, living status, family impact, and other aspects, and some findings were mentioned in only one study. The clinical trial resulted in no functional status changes among case managed subjects, despite an extended period of rehabilitation (Greenwood and Brooks, 1994). However, when two forms of case management were compared, both the single and multiple case manager/insurance approaches showed significant functional improvements (Ashley, Krych, Persel, et al., 1994).
Findings also conflicted on the effect of case management on subjects' living arrangements. Greater independence was demonstrated with the single case manager and insurance approach (Ashley, Krych, Persel, et al., 1993), while greater dependence was found with the general case manager model (Greenwood and Brooks, 1994). In the only study that measured the effect of case management on families, the result was that families sought more medical care, and they changed their amount of leisure time (although the direction was not identified) (Greenwood and Brooks, 1994). A modest majority of respondents in the Malec, Buffington, Moessner, et al. (1995) study found the case manager helpful, but the report did not mention whether this rating referred to the nurse case manager and/or the vocational case manager. Single-study findings included lower rehabilitation costs and higher disability payments for the single case manager model (Ashley, Krych, Persel, et al., 1993) and identification of unmet case management needs among adolescents, seniors, and alcoholic clients (Malec, Buffington, Moessner, et al., 1995).
Conclusions for Question 5
From our review we conclude that there is no clear evidence that case management is effective with survivors of TBI and their families, but neither is there clear evidence that it is ineffective. Further research is warranted to resolve this question. It is not possible to directly compare the three studies reviewed because there were almost no similarities in design, sampling, or outcome measures that would provide a basis for comparison. Although all 312 subjects had been diagnosed with brain injury and had evidence of impairment, the samples represent different subpopulations based on injury severity level: moderate, severe, and mixed. For the latter sample, results were not reported by level of injury. Similarly, although there was a controlled intervention of case management provided in each study, there were key differences in the definitions and case management model characteristics. In addition, there were few, if any, specifications about the case managers' training, discipline, experience, and roles. Only one report (Greenwood and Brooks, 1994) mentioned the number of case managers who had provided the intervention (three), and it also was the only report that mentioned the number of clients that were managed by each case manager at one time (20). In no case was there any evidence of reliability or validity testing of the case management approach.
In addition, there are other weaknesses that contribute to the inability to draw conclusions from this small group of studies. One potential source of bias is the lack of control for cointerventions that may have provided service referrals, care continuity, and client and/or family support that simulated case management. This might have occurred, for example, when a study case manager referred the client to another program or service, and it also may have occurred within the family support system. Without controlling for such an effect, it is not possible to attribute any results to formal case management. Another problem is that the studies each provided case management for different amounts of time and at different stages of recovery. Moreover, they utilized different periods of time to measure the outcomes, and the measures did not continue longitudinally for all subjects. This had the statistical effect of reducing the number of subjects who were likely to benefit from the intervention. That is, even if the intervention did have a positive effect, the difference may not have been apparent. Also, because of the team-oriented nature of case management coordination, none of the researchers were able to arrange blind assessments of the subjects. For this reason, it is not possible to know whether there are provider biases associated with care provided for particular subjects or subject groups.
Finally, nothing is known about the quality of the rehabilitation programs associated with the case management models demonstrated in the reviewed studies. Greenwood and Brooks (1994) point out that since the experimental subjects did not progress despite greater rehabilitation service contact time, the cause may have been that the case manager did not have the authority to improve the quality of rehabilitation. Since client and family outcomes may be related only to rehabilitation program benefit, it would be useful to know how to control for rehabilitation program quality to identify confounding factors. Another consideration for possible effect on the targeted outcomes is the ability to access the rehabilitation programs. Since rehabilitation access depends on program availability in the community, economic feasibility for the patient, and the knowledge of others--such as family physicians and emergency care teams--it would be useful to have measures of those environmental conditions as additional outcome analysis controls.
Despite these methodological weaknesses and the incompatible findings, however, there are some observations that can be made from the collective findings of these three studies. First, two of the three studies found significant improvements associated with case management in at least one type of functional outcome (Ashley, Krych, Persel, et al., 1994; Malec, Buffington, Moessner, et al., 1995). This suggests that perhaps the model of case management that was employed in the Greenwood and Brooks (1995) study was simply the wrong model. Second, in the Greenwood and Brooks (1995) study, the dropout rate among subjects without a case manager was higher, which suggests that subjects may have found the service useful in a subjective way. These glimmers of evidence from three controlled studies provide substantive implications for continued research that can improve upon the methods described above.
Future Research on Question 5
Research studies in the future need to test for possible effects of case management that have not yet been identified. We believe it is important to conduct clinical trials that specify and test the extent of contact with the client and family, role training and competence, service-approval authority, screening/rescreening frequency, and influence within the rehabilitation community network. Reliability and validity testing also are recommended for measuring case management. In addition, controls should be in place for isolating possible cointerventions that simulate care coordination. The control variables should include postinjury rehabilitation elements such as settings, types of therapies, amount of contact times, goal achievement records, and other aspects that may directly affect client outcomes.
We suggest that there be improved outcome measures used in case management clinical trial studies for TBI subjects. In addition to outcomes of changed client functionality, there should be outcomes of changed family functionality. Since much of case management communication is directed toward helping family members learn what to expect and where to obtain services, relevant outcomes would include family use of community and rehabilitation services and indicators of family assertiveness regarding care expectations. While case management may only indirectly affect a client's functional outcomes such as level of disability, vocational status, and living status, it is possible that case management can directly affect family knowledge of TBI rehabilitation needs and services, level of psychosocial anxiety, and family competency in coping with TBI.
We also recommend separate measures and analyses for subjects with mild, moderate, and severe disability. Greenwood and Brooks (1994) interpreted their findings that more case-managed-group relatives reported a major TBI effect on the family and had more use of prescribed drugs and medical services by attributing the differences to a more severely ill sample in the case-managed group. However, this could not be verified because they had not controlled for severity of illness. Third, if family members were measured at pre- and postintervention points, the case management intervention effects should become more apparent. Finally, for purposes of study comparability, outcomes could be measured at 12-month postinjury intervals.
- Question 1: Should interdisciplinary rehabilitation begin during the acute hospitalization for traumatic brain injury?
- Question 2: Does the intensity of inpatient interdisciplinary rehabilitation affect long-term outcomes?
- Question 3: Does the application of compensatory cognitive rehabilitation enhance outcomes for people who sustain TBI?
- Question 4: Does the application of supported employment enhance outcomes for people with TBI?
- Question 5: Does the provision of long-term care coordination enhance the general functional status of people with TBI?
- Results - Rehabilitation for Traumatic Brain InjuryResults - Rehabilitation for Traumatic Brain Injury
- Evidence Tables - Rehabilitation for Traumatic Brain InjuryEvidence Tables - Rehabilitation for Traumatic Brain Injury
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