Adaptation and validation of the Distress Scale for Mexican patients with type 2 diabetes and hypertension: a cross-sectional survey

OBJECTIVES: The aim of this study was to adapt and validate the Distress Scale for Mexican patients with type 2 diabetes and hypertension (DSDH17M). SETTING: Two family medicine clinics affiliated with the Mexican Institute of Social Security. PARTICIPANTS: 722 patients with type 2 diabetes and/or hypertension (235 patients with diabetes, 233 patients with hypertension and 254 patients with both diseases). DESIGN: A cross-sectional survey. METHODS: The validation procedures included: (1) content validity using a group of experts, (2) construct validity from exploratory factor analysis, (3) internal consistency using Cronbach's α, (4) convergent validity between DSDH17M and anxiety and depression using the Spearman correlation coefficient, (5) discriminative validity through the Wilcoxon rank-sum test and (6) test–retest reliability using intraclass correlation coefficient. RESULTS: The DSDH17M has 17 items and three factors explaining 67% of the total variance. Cronbach α ranged from 0.83 to 0.91 among factors. The first factor of ‘Regime-related Distress and Emotional Burden’ moderately correlated with anxiety and depression scores. Discriminative validity revealed that patients with obesity, those with stressful events and those who did not adhere to pharmacological treatment had significantly higher distress scores in all DSDH17M domains. Test–retest intraclass correlation coefficient for DSDH17M ranged from 0.92 to 0.97 among factors. CONCLUSIONS: DSDH17M is a valid and reliable tool to identify distress of patients with type 2 diabetes and hypertension.