title: Optimizing detection of major depression among patients with coronary artery disease using the patient health questionnaire: data from the heart and soul study.
abstract: BACKGROUND
  Clinical guidelines recommend depression screening in patients with coronary artery disease (CAD), but how to accomplish this is unclear.
  
  
  OBJECTIVE
  We evaluated the test characteristics of the two-item Patient Health Questionnaire (PHQ-2), the nine-item Patient Health Questionnaire (PHQ-9), and a two-step screening approach (PHQ-2 then PHQ-9 if positive on PHQ-2), compared with the Computerized Diagnostic Interview Schedule (C-DIS) for major depression. We also evaluated a "PHQ diagnosis" of depression, requiring five of nine symptoms "more than half the days," compared with the C-DIS.
  
  
  METHODS
  Cross-sectional study of 1,024 outpatients with CAD.
  
  
  RESULTS
  Two hundred twenty-four patients (22%) had current major depression. Optimal cutpoints were >or=2 for the PHQ-2 (82% sensitive, 79% specific) and >or=6 for the PHQ-9 (83% sensitive, 76% specific). The two-step screening approach was less sensitive (75%), but more specific (84%), than the PHQ-2 or PHQ-9 alone. The "PHQ diagnosis" had low sensitivity (28%), but high specificity (96%).
  
  
  CONCLUSIONS
  Cutpoints of >or=2 on the PHQ-2 and >or=6 on the PHQ-9 had similar test characteristics. A two-step approach using the PHQ-2 followed by the PHQ-9 was no better than either instrument alone. A "PHQ diagnosis" of depression had high specificity, but poor sensitivity.
authors.affiliation: Department of Psychiatry, McGill University and Sir Mortimer B Davis-Jewish General Hospital, Montreal, QC, Canada. brett.thombs@mcgill.ca
authors.forename: Brett D
authors.initials: BD
authors.lastname: Thombs
authors.forename: Roy C
authors.initials: RC
authors.lastname: Ziegelstein
authors.forename: Mary A
authors.initials: MA
authors.lastname: Whooley
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003324:Coronary Artery Disease / Q000150:complications / Q000523:psychology*; D003430:Cross-Sectional Studies; D003865:Major Depressive Disorder / Q000150:complications / Q000175:diagnosis* / Q000523:psychology*; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged