Reliability and Structure of Diabetes Diet Adherence Scale (D-DAS): A Follow-up Study among Type 2 Diabetes Patients of India

Introduction Measuring dietary adherence is essential while prescribing a diet plan for type 2 diabetes. This study aims to develop and validate a diabetes diet adherence scale (D-DAS) among type 2 diabetes patients in India. Methods A four-month non-randomised follow-up study was conducted among (n=120) type 2 diabetes patients attending the outpatient clinic. The adherence to the prescribed diet plan was determined using the D-DAS scale, and the impact of the prescribed diet plan was assessed at the endline. Multiple correspondence analysis (MCA) was used to determine the underlying dimensions of the scale, and confirmatory factor analysis (CFA) with multiple reliability measures was used to determine the reliability and construct validity of the scale. Results Adherence was 53.85%, and no significant difference was observed in baseline and endline fasting blood glucose. MCA revealed dimensions explaining 68.4% of the variance. CFA showed high reliability (McDonald’s ω and Guttman’s λ2=0.836). D-DAS demonstrated a reliable underlying construct (composite reliability=0.90, average variance explained=0.56). Conclusion D-DAS is a reliable and valid scale for measuring dietary adherence among type 2 diabetes patients in India. Adherence was moderate, suggesting the need for targeted interventions to improve dietary compliance and diabetes management.