Detecting Depression and Anxiety Among Adolescents in South Africa: Validity of the isiXhosa Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7

Screening tools such as the Patient Health Questionnaire-9 (PHQ-9) and the Generalized Anxiety Disorder-7 (GAD-7) could potentially be used in resource-limited settings to identify adolescents who need mental health support. We examined the criterion validity of the isiXhosa versions of the PHQ-9 and GAD-7 in detecting depression and anxiety among adolescents (10–19 years) in South Africa. Adolescents were recruited from the general population and from nongovernmental organizations working with adolescents in need of mental health support. The PHQ-9 and GAD-7 were culturally adapted and translated into isiXhosa and administered to 302 adolescents (56.9% female). The Kiddie Schedule for Affective Disorders and Schizophrenia was administered by trained clinicians as the gold standard diagnostic measure for depression and anxiety. For the PHQ-9, the area under the curve was 0.88 for the full sample of adolescents (10–19 years old). A score of ≥10 had 91% sensitivity and 76% specificity for detecting adolescents with depression. For the GAD-7, the area under the curve was 0.78, and cutoff scores with an optimal sensitivity-specificity balance were low (≥6). A score of ≥6 had 67% sensitivity and 75% specificity for detecting adolescents with anxiety. The culturally adapted isiXhosa version of the PHQ-9 can be used as a valid measure for depression in adolescents. Further research on the GAD-7 for use with adolescents is recommended.