title: Screening for anxiety disorders with the GAD-7 and GAD-2: a systematic review and diagnostic metaanalysis.
abstract: OBJECTIVE
  To systematically review the accuracy of the GAD-7 and GAD-2 questionnaires for identifying anxiety disorders.
  
  
  METHODS
  A systematic review of the literature was conducted to identify studies that validated the GAD-7 or GAD-2 against a recognized gold standard diagnosis. Pooled estimates of diagnostic test accuracy were produced using random-effects bivariate metaanalysis. Heterogeneity was explored using the I(2) statistic.
  
  
  RESULTS
  A total of 12 samples were identified involving 5223 participants; 11 samples provided data on the accuracy of the GAD-7 for identifying generalized anxiety disorder (GAD). Pooled sensitivity and specificity values appeared acceptable at a cutoff point of 8 [sensitivity: 0.83 (95% CI 0.71-0.91), specificity: 0.84 (95% CI 0.70-0.92)] although cutoff scores 7-10 also had similar pooled estimates of sensitivity/specificity. Six samples provided data on the accuracy of the GAD-2 for identifying GAD. Pooled sensitivity and specificity values appeared acceptable at a cutoff of 3 [sensitivity: 0.76 (95% CI 0.55-0.89), specificity: 0.81 (95% CI 0.60-0.92)]. Four studies looked at the accuracy of the questionnaires for identifying any anxiety disorder.
  
  
  CONCLUSIONS
  The GAD-7 had acceptable properties for identifying GAD at cutoff scores 7-10. The GAD-2 had acceptable properties for identifying GAD at a cutoff score of 3. Further validation studies are needed.
authors.affiliation: Department of Health Sciences, University of York, York YO10 5DD, United Kingdom.
authors.forename: Faye
authors.initials: F
authors.lastname: Plummer
authors.affiliation: Hull York Medical School and Department of Health Sciences, University of York, York YO10 5DD United Kingdom.
authors.forename: Laura
authors.initials: L
authors.lastname: Manea
authors.affiliation: Department of Health Sciences, University of York, York YO10 5DD, United Kingdom.
authors.forename: Dominic
authors.initials: D
authors.lastname: Trepel
authors.affiliation: Hull York Medical School and Department of Health Sciences, University of York, York YO10 5DD United Kingdom. Electronic address: dean.mcmillan@york.ac.uk.
authors.forename: Dean
authors.initials: D
authors.lastname: McMillan
mesh_terms: D001008:Anxiety Disorders / Q000175:diagnosis*; D006801:Humans; D011569:Psychiatric Status Rating Scales / Q000592:standards*
keywords: Anxiety; Diagnostic test accuracy; Generalised anxiety disorder; Sensitivity and specificity; Systematic review