Diabetes-related emotional distress in adults: Reliability and validity of the Norwegian versions of the Problem Areas in Diabetes Scale (PAID) and the Diabetes Distress Scale (DDS)

Background: Regular assessment of diabetes-related emotional distress is recommended to identify high-risk people with diabetes and to further prevent negative effects on self-management. Nevertheless, psychological problems are greatly under diagnosed. Translating and testing instruments for psychosocial assessment across languages, countries and cultures allow for further research collaboration and enhance the prospect of improving treatment and care. Objectives: To examine the psychometric properties of the Norwegian versions of the Problem Areas in Diabetes Scale and the Diabetes Distress Scale. Design: Cross-sectional survey design. Settings: A sample comprising adults with diabetes (response rate 71%) completed the Problem Areas in Diabetes Scale and the Diabetes Distress Scale, which were translated into Norwegian with standard forward-backwards translation. Participants: The study included 292 participants with type 1 (80%) and type 2 diabetes (20%) aged 18-69 years, 58% males, mean diabetes duration 17.3 years (11.6), mean HbA(1c) 8.2% (1.6). Methods: We used exploratory factor analysis with principal axis factoring and varimax rotation to investigate the factor structure and performed confirmatory factor analysis to test the best fit of a priori-defined models. Convergent and discriminate validity were examined using the Short Form-36 Health Survey, Hospital Anxiety and Depression Scale and demographic and disease-related clinical variables. We explored reliability by internal consistency and test-retest analysis. Results: Exploratory factor analysis supported a four-factor model for the Diabetes Distress Scale. Confirmatory factor analysis indicated that the data and the hypothesized model for the Diabetes Distress Scale fit acceptably but not for the Problem Areas in Diabetes Scale. Greater distress assessed with both instruments correlated moderately with lower health-related quality of life and greater anxiety and depression. The instruments discriminated between those having additional health conditions or disabilities, foot problems or neuropathy. Women and participants with higher HbA(1c) levels reported significantly higher diabetes-related emotional distress. Conclusions: The Norwegian versions of the Problem Areas in Diabetes Scale and the Diabetes Distress Scale have satisfactory psychometric properties and can be used to map diabetes-related emotional distress for diagnostic or clinical use. The Diabetes Distress Scale also contributes to identifying sub-domains of distress and seems promising for use in clinical trials. (C) 2011 Elsevier Ltd. All rights reserved.