Reliability and Validity of Vietnamese Version of Patient Health Questionnaire 9 Items (PHQ-9) Among UMP Medical Freshmen

Patient Health Questionnaire (PHQ–9) is a global tool that can be effective for depression screening, especially in the context of high prevalence of the disorder in medical students. The aims of this study are: (1) Translating and cultural adapting the Vietnamese version of PHQ-9; (2) Establishing reliability and (3) Identifying validity of PHQ-9 Vietnamese version within Vietnamese medical students. The process of establishing the PHQ-9 Vietnamese version strictly followed the international guideline for translation and cultural adaptation of psychometric instruments recommended by WHO. Four hundred two medical freshmen were involved in PHQ-9 study for internal reliability. After 10 days, 76 students from the former list were randomly selected for a structured interview with psychiatrists and underwent repeated PHQ-9 test. Records of the latter time were used to calculate test–retest reliability and criteria validity. ROC curve analysis was performed to evaluate diagnostic efficiency. High internal and test–retest consistency for PHQ-9 (Cronbach’s alpha as 0.81 and Spearman correlation coefficient as 0.83) were identified. The sensitivity and specificity at the cut-off 12 were 71% and 93%, and 7 was 82% and 71%, respectively. The reliability and validity of PHQ-9 Vietnamese version are advisable for applying in mental health management for medical freshmen. The cut-off score is 12 for epidemiological purposes and is 7 for screening purposes. Further researches should assess PHQ-9 Vietnamese version’s psychometric features towards other medical college groups or other forms of handling tests, listing as mobile apps or web-based systems.