Optimal cut-off score for diagnosing depression with the Patient Health Questionnaire (PHQ-9): a meta-analysis

Background:

The brief Patient Health Questionnaire (PHQ-9) is commonly used to screen for depression with 10 often recommended as the cut-off score. We summarized the psychometric properties of the PHQ-9 across a range of studies and cut-off scores to select the optimal cut-off for detecting depression.

Methods:

We searched Embase, MEDLINE and PsycINFO from 1999 to August 2010 for studies that reported the diagnostic accuracy...