Psychometric properties of the Persian version of the treatment satisfaction questionnaire for medication (TSQM) among Iranian hypertensive patients

Objective: This study aimed to evaluate the psychometric properties of the Persian version of the TSQM-14 in patients with hypertension in Iran Methods: This cross-sectional study was conducted among hypertensive patients referred to primary healthcare centers in Kerman City between January and February 2021. Cronbach's alpha and total-item correlation were used to evaluate internal consistency, while the Intraclass Correlation Coefficient (ICC) was employed to assess test-retest reliability. Construct validity was examined using structural equation modeling (SEM), known-groups validity, and convergent validity. Results: A total of 319 participants took part in the study, with a mean age of 56.7 years (SD = 13.0), and 57.7% (n = 184) were female. The Cronbach's alpha and ICC values of the TSQM-14 for the composite scales were 0.83 and 0.91, respectively, indicating good reliability. The SEM indices for TSQM-14 demonstrated adequate model fit, with chi(2) = 118.9 (P <= 0.001), CFI = 0.96, RMSEA = 0.07, TLI = 0.95, and NFI = 0.91. The mean (standard deviation (SD)) scores of the composite scale for patients in the uncontrolled group (systolic blood pressure >= 140 mmHg or diastolic blood pressure >= 90 mmHg) and the controlled group were 50.2 (SD = 6.6) and 47.6 (SD = 6.1), respectively (P = 0.021). Additionally, the Spearman correlation coefficient between the TSQM-14 scale and the MMAS-8 was 0.30 (P < 0.001), demonstrating a weak but significant correlation. Conclusions: This study demonstrated that the Persian version of the TSQM-14 has acceptable reliability, as well as construct and convergent validity, for assessing treatment satisfaction among hypertensive patients.