Psychometric Properties of the Persian Version of the Quality-of-Life Questionnaire in Patients Receiving Opioid Substitution Treatment

Abstract

Background: Quality of life (QoL) is increasingly recognized as a significant component in the monitoring of clinical interventions. However, no specific tool is available in the Persian language to assess the QoL in patients treated with opioid agonists. Objectives: To systematically translate the QoL Questionnaire in patients receiving opioid substitution treatment quality-of-life (OSTQOL) into Persian and assess the validity and reliability of the translated version. Methods: An analytical cross-sectional study was carried out on 380 adult males receiving opioid substitution treatment (OST) at substance abuse treatment centers in the city of Rasht, Iran, in the year 2021. The reliability of the Persian version of the questionnaire was assessed using Cronbach's alpha, McDonald’s Omega, and test-retest reliability. Content validity was evaluated by a panel of experts, and structural validity was assessed through confirmatory factor analysis (CFA). Results: The fit indices obtained in the CFA were acceptable (CMIN/DF = 2.34, GFI = 0.82, RMSEA = 0.06, NFI = 0.95, CFI = 0.97). The Cronbach's alpha and McDonald’s Omega coefficients for the tool, and the intraclass correlation coefficient (ICC) and test-retest coefficient were 0.926, 0.918, 0.943, and 0.996, respectively, indicating excellent reliability of the instrument. Conclusions: The Persian version of the OSTQOL is a valid and reliable tool for measuring the QoL of patients undergoing OST. Therefore, QoL researchers will be able to specifically measure QoL among patients receiving opioid agonists.