Reliability and validity of the Chinese version of the Patient Health Questionnaire (PHQ-9) in the general population

Abstract Objective Depression is one of the most common mental illnesses. The reliability and the validity of the Patient Health Questionnaire (PHQ)-9, a depression screening tool, have not been examined in the general population in China. Thus, this study evaluated the reliability and the validity of the Chinese version of the PHQ-9 in detecting major depression in residents of a Chinese community. Methods A total of 1045 participants from a Shanghai community were enrolled in our study. Participants completed the Chinese versions of the PHQ-9, the Self-Rating Depression Scale (SDS), the 36-item Short Form Health Survey (SF-36), and the Mini International Neuropsychiatric Interview. One hundred participants were randomly selected to complete the PHQ-9 again 2 weeks after the initial assessment. The reliability, the validity and the receiver operating characteristic (ROC) curve of the PHQ-9 were analyzed. Results Cronbach's alpha for the internal consistency reliability of the Chinese version of the PHQ-9 was 0.86 for the entire scale. The correlation coefficient for the 2-week test–retest of the total score was 0.86. The PHQ-9 scale correlated positively with the SDS ( r =0.29, p p Conclusions In the general Chinese population, the Chinese version of the PHQ-9 is a valid and efficient tool for screening depression, with a recommended cutoff score of 7 or more.