Diagnostic discriminative accuracy and cut-off values of the Arabic-language PHQ-9 in a treatment-seeking mental health sample.

THEORETICAL

Background

The PHQ-9 is a widely used international screening instrument for depressive disorders, but optimal cut-off values vary depending on population and geographical region. RESEARCH QUESTION This study aims to evaluate the psychometric properties and diagnostic accuracy of the Arabic PHQ-9 and identify the threshold with the best discrimination of current major depressive episode (MDE).

Method

In this prospective diagnostic accuracy study, 2298 individuals were included as a convenience sample as part of an intake screening for an Arabic-language therapy project. Participants completed questionnaires and underwent a telephone-based SCID-5-CV interview, which served as the reference standard; the PHQ-9 served as the index test. Psychometric properties were assessed using EFA and CFA, and diagnostic accuracy was evaluated using ROC analyses.

Results

Of the 2298 participants included in the analyses, 1967 met SCID-5-CV criteria for a current MDE, while 331 did not. The psychometric evaluation yielded satisfactory values overall. The AUC was 0.71 (95% CI = 0.69-0.75). The highest sensitivity was observed at a cut-off of 10 (Se = 0.93, Sp = 0.34), while the Youden Index indicated that a cut-off of 14 provided the best balance between sensitivity (0.76) and specificity (0.56).

Conclusion

Given that high sensitivity is central in clinical studies, the Arabic PHQ-9 is suitable as a first step in a stepped screening procedure, but not for diagnostic decision-making. Cut-off values from other linguistic versions cannot be automatically transferred and must instead be validated specifically for each language version. REGISTRATION DRKS00016652.