A computerized version of the Patient Health Questionnaire-4 as an ultra-brief screening tool to detect emotional disorders in primary care.

BACKGROUND: The Patient Health Questionnaire-4 (PHQ-4) is an ultra-brief self-report consisting of a 2-item depression scale (PHQ-2) and a 2-item anxiety scale (GAD-2). The aim of the present study is to determine the psychometric properties of a computerized version of the PHQ-4 used to detect emotional disorders (anxiety and depression) in the primary care setting.

METHOD: A total of 1052 patients with suspected anxiety, depression, or somatic symptoms were recruited from 28 primary care centres participating in the PsicAP trial and completed the full version of the computerized PHQ. In addition, 178 of these patients also underwent in clinical interviews as a gold standard.

RESULTS: Confirmatory factor analyses showed very good fit indices for a two-factor solution. This model was structurally invariant among the various age and gender groups and internal consistency was acceptable (PHQ-4; α = .83, PHQ-2; α = .86, and GAD-2; α = .76). The best cut-off points to obtain high sensitivity values was 3, on both the PHQ-2 (major depressive disorder) and the GAD-2 (generalized anxiety disorder). The criterion validity (sensitivity and specificity) for the PHQ-2 were .90 and .61 and for the GAD-2, .88 and 0.61.

LIMITATIONS: The study was not designed as a prevalence study. Therefore, does not contain information on patients whose general practitioners do not consider them to suffer emotional disorders.

CONCLUSION: This is the first study to provide evidence for the reliability and validity of a computerized version of the PHQ-4. This computerized tool can be used to detect depression and anxiety in a primary care setting.