Screening for depressive disorders: Validation of the Patient Health Questionnaire for Adolescents (PHQ-A) in a population-based multi-ethnic Asian sample

Objective: 

To validate the Patient Health Questionnaire for Adolescents (PHQ-A) as a screening tool for depressive disorders in multi-ethnic Asian adolescents. 

Methods: 

323 English-speaking Singaporean adolescents completed the PHQ-A, Kiddie Schedule for Affective Disorders and Schizophrenia Present and Lifetime Version (K-SADS-PL), and measures of depressive symptoms (Hamilton Depression Rating Scale), suicidality (Columbia Suicide Severity Rating Scale), adverse childhood experiences (ACES), and quality of life (Youth Quality of Life Instrument – Short Form) as part of a larger nationwide cross-sectional school-based epidemiological study. Internal consistency, construct validity, and diagnostic accuracy of the PHQ-A were evaluated. The area under the ROC curve (AUC) values for Major Depressive Disorder (MDD), Persistent Depressive Disorder (PDD), and Adjustment Disorder (AD) were examined separately. 

Results: 

The PHQ-A demonstrated high internal consistency (Cronbach's α = 0.89) and was positively associated with adverse childhood experiences (ρ = 0.11, p = 0.042), suicidality (ρ = 0.43, p < 0.001), and depressive symptoms (ρ = 0.63, p < 0.001), and negatively associated with quality of life (ρ = -0.59, p < 0.001). The performance of the PHQ-A was acceptable for MDD (AUC = 0.79, 95 % CI = 0.72 - 0.85) but poorer for PDD (AUC = 0.68, 95 % CI = 0.58 – 0.77) and AD (AUC = 0.53, 95 % CI = 0.41 – 0.65). 

Conclusion: 

The PHQ-A shows acceptable psychometric properties for screening for diagnosis of MDD, but not for PDD or AD, among English-speaking Asian adolescents. A cut-off score of ≥ 10 for MDD is recommended.