Validity and Reliability of the Turkish Version of the Glucose Monitoring Satisfaction Survey

Objective: The Glucose Monitoring Satisfaction Survey (GMSS) is crucial for assessing diabetes management, but its psychometric properties in Turkish patients remain unexplored. This study aimed to evaluate the validity and reliability of the Turkish version of the GMSS. Material and Method: This methodological, descriptive, and correlational study was conducted with 220 patients with type 1 diabetes between October 2023 and February 2024. Data were collected online using a sociodemographic questionnaire, the GMSS, and the WHO-5 Well-Being Index. Statistical analyses were performed with IBM SPSS v27 and IBM SPSS Amos v24. Reliability was evaluated with Cronbach’s alpha coefficients for the overall scale and each subscale, Spearman-Brown Split-Half analysis, item–total correlations, and “Cronbach’s alpha if item deleted.” Validity was examined through language validity, expert-based content validity, and construct validity using Confirmatory Factor Analysis (CFA). Assumptions for CFA were checked, and the maximum likelihood method was applied. Parallel form reliability was also assessed with WHO-5. Results: Item-level content validity indexes ranged between 0.80 and 1.00, while the scale-level index was 0.960. Cronbach’s alpha was 0.897 for the overall scale and ranged between 0.85 and 0.90 across the four subscales. Item–total correlations varied from 0.347 to 0.719, and “alpha if item deleted” values remained above 0.85. The Spearman-Brown Split-Half coefficient was 0.885. CFA supported the four-factor model with acceptable fit indices. Parallel form reliability showed significant positive correlations between the GMSS and WHO-5 (p