DEVELOPMENT OF A TYPE-2 DIABETES SYMPTOM CHECKLIST - A MEASURE OF SYMPTOM SEVERITY

The aim of the present study was to develop a Type 2 diabetes symptom checklist for use in clinical and epidemiological research, which can measure differences in symptom severity between patients and detect ch anges over time within patients. Face and content validity of items an d dimension structure were based on literature and experiences of diab etologists. Two Likert scales were used to measure symptom frequency a nd perceived burden. Reliability, responsiveness and validity were stu died in 185 Type 2 diabetic patients. Factor-analysis confirmed the pr edesigned dimension structure with 34 items, distributed over 6 dimens ions. The internal consistency with Cronbach alpha coefficients betwee n 0.76 and 0.95 and test-retest reliability with Pearson product-momen t correlation coefficients between 0.79 and 0.94 were satisfactory. Th e ability to detect change over time (responsiveness) was estimated in stable subjects, using sample size calculations. A minimal detectable mean change of 0.07-0.58 points in total score on the 10-point scale within a group of 100 subjects suggests an impressive responsiveness. Significant differences in symptom severity score were found between p atients with different co-morbidity status and treatment modes, indica ting satisfactory construct validity of the dimension structure. The T ype 2 Diabetes Symptom Checklist was found to be a useful diabetes-spe cific symptom severity assessment method for clinical and epidemiologi cal studies.