Screening accuracy and psychometric properties of the whooley questions, Edinburgh postnatal depression scale, and patient health questionnaire-9 among pregnant women.

Objective

To compare the psychometric properties and diagnostic interview-validated screening accuracy of the Whooley Questions (WQ), Edinburgh Postnatal Depression Scale (EPDS), and Patient Health Questionnaire-9 (PHQ-9) among pregnant women in routine obstetric care.

Methods

This diagnostic accuracy study was conducted in a tertiary obstetric outpatient clinic in China from January to February 2025. A total of 557 consecutive pregnant women completed the WQ, EPDS, and PHQ-9, and 215 also completed a DSM-IV-based structured diagnostic interview as the reference standard. Internal consistency, structural validity, and diagnostic accuracy were evaluated.

Results

In this sample, the EPDS showed the highest discriminative accuracy and the clearest latent structure, whereas the PHQ-9 showed weaker structural validity. The WQ and PHQ-9 showed higher specificity and lower screen-positive rates than the EPDS, suggesting potential utility as brief triage tools when rapid screening or reduced follow-up burden is prioritized. However, because few depression cases were confirmed by diagnostic interview, comparative accuracy estimates should be interpreted cautiously.

Conclusions

In this Chinese antenatal sample, the three instruments showed different psychometric and diagnostic performance profiles. The EPDS may be useful when sensitivity is prioritized, whereas the WQ and PHQ-9 may support brief triage or supplementary risk stratification in time-limited settings. These findings support context-adapted tool selection rather than reliance on a single optimal instrument for all antenatal screening purposes.