Background: Depression is a common comorbidity in patients with coronary artery disease (CAD), which often remains undetected and untreated. Objective: This study aimed to examine the psychometric properties of the Depression Module of the Patient Health Questionnaire (PHQ-9) on a sample of cardiac patients in Iran. Method: The Persian version of the PHQ-9 was developed and administered to 150 patients with CAD, admitted to a tertiary hospital in Tehran, Iran. The major depression module of the International Neuropsychiatric Interview (MINI) was used as the gold standard for the diagnosis of depression. Results: The Persian PHQ-9 demonstrated acceptable internal consistency, with Cronbach's alpha coefficient of 0.80. The optimal cut-off score of ≥7 showed a sensitivity of 76, specificity of 78, and the area under curve of 0.82. Conclusion: The Persian PHQ-9 has acceptable psychometric properties to screen for and detect a current depressive episode in patients with CAD, with recommended cut-off score of ≥7.
Keywords: coronary artery disease; depression; nursing; the PHQ-9; validation study.