Diagnosing depression in primary care using self-completed instruments: UK validation of PHQ-9 and CORE-OM

Abstract

There is increased emphasis on routine assessment of depression in primary care. This report is the first UK validation of two self-completed measures: the Patient Health Questionnaire (PHQ-9) and the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM). Optimum cut-off points were established against a diagnostic gold standard in 93 patients. PHQ-9 sensitivity = 91.7% (95% confidence interval [CI] = 77.5 to 98.3%) and specificity 78.3% (95% CI = 65.8 to 87.9%). CORE-OM sensitivity = 91.7% (95% CI = 77.5 to 98.2%) and specificity = 76.7% (95% CI = 64.0 to 86.6%). Brief self-rated questionnaires are as good as clinician-administered instruments in detecting depression in UK primary care.

Figure 1

Receiver Operator Characteristic (ROC) curve of CORE–OM (Clinical Outcomes in Routine Evaluation − Outcome Measure) depression scores; CORE–OM clinical scores; and Patient Health Questionnaire (PHQ–9) scores in the presence or absence of major depression diagnosed by the Structured Clinical Interview for DSM.