The Patient Health Questionnaire (PHQ-9) is a brief tool used to diagnose and measure severity of depression. The PHQ-9 is shorter than many of the other depression screening instruments and can be self-administered. Adapted from the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV), the PHQ-9 is comprised of the same diagnostic symptom criteria used in the DSM-IV:
Two cardinal signs of depression (anhedonia and depressed mood);
Cognitions (e.g. guilt/worthlessness and suicidality/thoughts of death); and
Physical symptoms (e.g. change in appetite, difficulty sleeping and concentrating, feeling tired/slowed down or restless).
Author*: Katie Marvin, MSc PT Candidate
Editors: Nicol Korner-Bitensky, PhD OT
Evidence reviewed as of before 11-01-2011