Validity of the patient health questionnaires (phq-2 and phq-9) for screening depression among human immunodeficiency virus patients in Lahore, Pakistan.

Background: Many human immunodeficiency virus (HIV) infected patients suffer from depr-ession, but a little focus is given to detecting and treating depression in primary health care. Detection of depression can be improved by introducing short, reliable, and valid screening instruments.

Aim: To determine the psychometric properties of the patient health questionnaire-2 (PHQ-2) and patient health questionnaire-9 (PHQ-9) for depression screening and diagnosis, and the sensitivity and specificity of the PHQ-2 in HIV infected patients.

Methods: A cross-sectional study was conducted on 158 HIV-infected patients aged 18 years and above in Lahore, Pakistan. PHQ-2 was implemented to screen depression. PHQ-9 was implemented to diagnose major depressive disorder as a reference standard. Reliability, Validity tests and receiver operating characteristic curve were computed.

Results: The Cronbach's alpha of PHQ-2 and PHQ-9 were 0.732 and 0.759, respectively. The study results showed that the score of 2 on PHQ-2 indicates the highest Youden's index of 0.924, with both sensitivity and specificity of 0.96, and the area under the curve for PHQ-2 was 0.98 (95%CI: 0.953-0.998).

Conclusion: Good psychometric properties for the PHQ-2 and PHQ-9 indicated their significant potential as tools for depression screening and diagnosis in the HIV-infected population.