Factor Structure of Persian Translation of the Patient Health Questionnaire in Iranian Earthquake Survivors

There is great need across the globe for self-report scales of depression that are brief to administer, comprehensive in content, and psychometrically valid. As most of the widely used and well-validated scales originate in English, it is essential to carefully translate them, following the psychometric validation of the adapted scales. The current study aimed at investigating the translation and validation of the Persian version of one of the most widely utilized self-report depression scales in the world, the patient health questionnaire (PHQ). The current study evaluated the validity and reliability of the PHQ in a population-based sample of 600 adult survivors of an earthquake in Iran in 2015. Researchers used the forward-backward method to translate the PHQ-9 into the Persian language. Data were analyzed using both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Consistent with the results of validation studies on the original English-language versions of the scales, the current study found strong evidence of internal consistency (Cronbach’s alpha = 0.86). CFA suggested that the 1-factor structure fit reasonably well. Convergent validity was confirmed by the significant and positive correlation between the scores of national stressful events survey for posttraumatic stress disorder-short scale (NSESSS-PTSD) and the PHQ-9 (r = 0.29, P < 0.001). Approximately one-third of the sample reported some depression symptoms, with less than 10% indicating moderately severe to severe symptoms. Although replication studies are needed, the current study results suggested that the Persian version of the PHQ-9 was a valid and reliable tool to efficiently, comprehensively, and accurately assess depression symptoms in the Iranian subjects.