Background: People with chronic health conditions are known to have a higher prevalence of depressive disorder. The Patient Health Questionnaire (PHQ-9) is a widely-used screening tool for depression which has not yet been validated for use on chronic care patients in South Africa.
Methods: A sample of 676 chronic care patients attending two primary health facilities in North West Province, South Africa were administered the PHQ-9 by field workers and a diagnostic interview (the Structured Clinical Interview for DSM-IV) (SCID) by clinical psychologists. The PHQ-9 and the PHQ-2 were evaluated against the SCID, as well as for sub-samples of patients who were being treated for HIV infection and for hypertension.
Results: Using the SCID, 11.4% of patients had major depressive disorder. The internal consistency estimate for the PHQ-9 was 0.76, with an area under the receiver operator curve (AUROC) of 0.85 (95% CI 0.82–0.88), which was higher than the AURUC for the PHQ-2 (0.76, 95% CI 0.73–0.79). Using a cut-point of 9, the PHQ-9 has sensitivity of 51% and specificity of 94%. The PHQ-9 AUROC for the sub-samples of patients with HIV and with hypertension were comparable (0.85 and 0.86, respectively).
Conclusions: The PHQ-9 is useful as a screening tool for depression among patients receiving treatment for chronic care in a public health facility.
Bhana, A.; Rathod, S.D.; Selohilwe, O.; Kathree, T.; Petersen, I. The validity of the Patient Health Questionnaire for screening depression in chronic care patients in primary health care in South Africa. BMC Psychiatry (2015) 15 (1) [DOI: 10.1186/s12888-015-0503-0]