Purpose
To investigate and compare how patients with diabetes mellitus and doctors rate the importance of outcomes used as part of composite endpoints in clinical diabetes trials. Secondly, to compare the ratings of outcomes between patients with low and high education.

Methods
Using a pre-piloted questionnaire, patients with diabetes and doctors working with diabetes were asked to rate the importance of 36 different outcomes commonly used in trials assessing intervention effects in patients with diabetes. The respondents were asked to rate individual outcomes as being either critical, of major importance, of moderate importance, or of minor importance.

Results
The study population consisted of 139 patients with a mean age of 56.6 years and an average duration of diabetes for 13.6 years and 45 doctors with a mean time of practice of 19.6 years. There was no difference between patients’ and doctors’ rating of risk of mortality and non-fatal myocardial infarction, and percutaneous coronary intervention (all p-values > 0.34). Non-fatal stroke, admission for heart failure or angina was perceived more severely by patients compared to doctors (all p-values < 0.03). Patients rated risk of foot-ulcers, amputations and quality of life as more important compared to doctors (p-values < 0.01).

Conclusion
The current study suggest that patients and doctors weigh some diabetic outcomes used as part of composite endpoints in clinical diabetes trials differently. These findings call for more studies on patient reported outcomes and patient education for improved personal care.