What is the best measure for assessing diabetes distress? A comparison of the Problem Areas in Diabetes and Diabetes Distress Scale: results from Diabetes MILES-Australia

This study used Rasch analysis to examine the psychometric validity of the Diabetes Distress Scale and the Problem Areas in Diabetes scale to assess diabetes distress in 3338 adults with diabetes (1609 completed the Problem Areas in Diabetes scale (n = 675 type 1 diabetes; n = 934 type 2 diabetes) and 1705 completed the Diabetes Distress Scale (n = 693 type 1 diabetes; n = 1012 type 2 diabetes)). While criterion and convergent validity were good, Rasch analysis revealed suboptimal precision and targeting, and item misfit. Unresolvable multidimensionality within the Diabetes Distress Scale suggests a total score should be avoided, while suboptimal precision suggests that the Physician-related and Interpersonal distress subscales should be used cautiously.