Strengths and weaknesses of our research

The strengths of this research arise mainly from our access two large data sets: the PODUS data set that was used to develop and validate the CPR and a SCI-Diabetes data set that was used to assess the transitional probabilities of people with diabetes mellitus moving from one risk state to another.

The weaknesses of the research relate to the large numbers of missing data in the SCI-Diabetes data set and the poor quality of some of the RCTs in the SR. It is also possible that the decision to separate the comparators by intervention may have modified our VOI analysis. An approach in which all interventions are considered together may well make RCTs more important in the VOI analysis, as they would inform the differences between preventative interventions and allow any interactions to be identified.

Overall conclusions

This research has led to development and validation of a simple CPR for use in clinical practice and an analysis of EHR data to show that the risk of foot ulceration does not change over a 10-year period for most people with diabetes mellitus. Our overview found that, although there are a large number of SRs of preventative interventions for foot ulceration, clear, reproducible conclusions were rare. Our new SR of trial data has allowed the identification of effective preventative interventions for foot ulceration in diabetes mellitus; digital thermometry and meta-analyses revealed the potentially beneficial effect of complex interventions and custom-made footwear and offloading. However, remains uncertainly remains about the clinical effectiveness and cost-effectiveness of interventions to prevent foot ulceration in diabetes mellitus.

We make the following recommendations for future research:

• There is a need for further research into the effectiveness and acceptability of and adherence to potential preventative DFU interventions.
• There is a need to better understand what constitutes ‘current practice’ in DFU prevention across the UK in terms of risk assessment methods (risk factors and how they are assessed), interventions offered and adherence to clinical guidelines.
• There is a need for more complete EHR data to be collected, particularly on those parameters relating to foot disease in diabetes mellitus.
• We recommend that researchers share their trial data for IPD analyses to explore subgroup effects for interventions.
• Further research using the new CPR is merited, as is treating all patients attending a foot screening clinic with a ‘treat-all patients attending foot screening’ strategy compared with care using a CPR.
• The effectiveness of combined treatments for specific risk groups and used at alternative frequencies should be explored further. To address the uncertainty surrounding treatment efficacy, a RCT would be required; however, the size, duration and cost of a RCT in this area require careful consideration.
• Further research aimed at comparing different prognostic models would be welcome.