Validity and reliability of Patient Health Questionnaire-9 and Patient Health Questionnaire-2 to screen for depression among college students in China.
INTRODUCTION
This study examined the validity and reliability of the Patient Health Questionnaire-9 (PHQ-9) and Patient Health Questionnaire-2 (PHQ-2). The optimal cutoff score when screening for depression among Chinese college students was also determined.


METHODS
A total of 959 participants completed the PHQ-9 and the Beck Depression Inventory (BDI) questionnaire. The Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders was used to diagnose depression. Statistical tests were performed to determine the reliability, validity, and receiver operating characteristic curve of the data. The concurrent validity was tested by examining associations between PHQ-9 and BDI. The sensitivity and specificity, as well as the positive and negative predictive values, were calculated for different cutoff scores of PHQ-9 and PHQ-2.


RESULTS
The internal consistency values of PHQ-9 and PHQ-2 were 0.854 and 0.727, respectively. The test-retest reliability values of PHQ-9 and PHQ-2 were 0.873 and 0.829, respectively. The scores of PHQ-9 (r = 0.790) and PHQ-2 (r = 0.651) were significantly associated with that of BDI. PHQ-9 had an optimal cutoff score of 11, which indicated a sensitivity of 0.89 and a specificity of 0.97, with an area under the curve of 0.977 (95% confidence interval: 0.966-0.988). The PHQ-2 demonstrated satisfactory sensitivity (0.81) and specificity (0.96) at the cutoff score of 3, and its area under the curve was 0.939.


DISCUSSION
The PHQ-9 and the PHQ-2 are valid and reliable tools to screen depression in Chinese college students. For screening purposes, cutoff scores of 11 and 3 are recommended for PHQ-9 and PHQ-2, respectively.
['Zhang|Ying-Li|YL|', 'Liang|Wei|W|', 'Chen|Zuo-Ming|ZM|', 'Zhang|Hong-Mei|HM|', 'Zhang|Jian-Hong|JH|', 'Weng|Xiao-Qin|XQ|', 'Yang|Shi-Chang|SC|', 'Zhang|Lei|L|', 'Shen|Li-Juan|LJ|', 'Zhang|Ya-Lin|YL|']
D000293:Adolescent D000328:Adult D002681:China D003866:Depressive Disorder D005163:Factor Analysis, Statistical D005260:Female D006801:Humans D007406:Interview, Psychological D008297:Male D008403:Mass Screening D015995:Prevalence D011569:Psychiatric Status Rating Scales D011594:Psychometrics D015203:Reproducibility of Results D012680:Sensitivity and Specificity D017678:Sex Distribution D013334:Students D011795:Surveys and Questionnaires D014495:Universities D055815:Young Adult
screening depression college student PHQ-9 PHQ-2