Comparison of the Usefulness of the PHQ-8 and PHQ-9 for Screening for Major Depressive Disorder: Analysis of Psychiatric Outpatient Data
- Author:
Cheolmin SHIN
1
;
Seung Hoon LEE
;
Kyu Man HAN
;
Ho Kyoung YOON
;
Changsu HAN
Author Information
- Publication Type:Original Article
- Keywords: Depression; Major depressive disorder; PHQ-8; PHQ-9
- MeSH: Area Under Curve; Depression; Depressive Disorder, Major; Humans; Mass Screening; Outpatients; Reproducibility of Results; Retrospective Studies; ROC Curve; Sensitivity and Specificity
- From:Psychiatry Investigation 2019;16(4):300-305
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVE: This study aimed to demonstrate that the Patient Health Questionnaire (PHQ)-8 is not less useful than the PHQ-9 as a screening test for major depressive disorder (MDD). METHODS: We performed a retrospective analysis of 567 patients in psychiatric outpatient units. The Mini International Neuropsychiatric Interview was used to diagnose MDD. We derived the validity and reliability of the PHQ-8 and PHQ-9. To evaluate the ability of the PHQ-8 and PHQ-9 to discriminate MDD, we drew receiver operating characteristic (ROC) curves and compared the areas under the curves (AUCs). RESULTS: Of the 567 participants, 207 (36.5%) were diagnosed with MDD. Cronbach’s αs for the PHQ-8 and PHQ-9 were 0.892 and 0.876, respectively. Similar to the PHQ-9, the PHQ-8 was also associated with scores on the Hamilton Depression Rating Scale in a correlation analysis. When we drew ROC curves for the PHQ-8 and PHQ-9, there was no statistically significant difference in the AUCs. With a cutoff score of 10, the PHQ-8 showed a sensitivity of 58.3%, specificity of 83.1%, positive predictive value of 53.4%, and negative predictive value of 85.7%. CONCLUSION: In a psychiatric outpatient sample, the PHQ-8 was as useful as the PHQ-9 for MDD screening.
