title: Quick and easy self-rating of Generalized Anxiety Disorder: validity of the Dutch web-based GAD-7, GAD-2 and GAD-SI.
abstract: Screening of Generalized Anxiety Disorder (GAD), which is often undetected and untreated, could be improved by quick and easy web-based data collection. This paper aims to validate the web-based self-rated 7-item GAD-7, its shortened 2-item GAD-2 and a single item from the GAD-7 scale (GAD-SI) to screen for GAD. Of a total of 502 subjects aged 18-80 who rated the web-based GAD-7, Center for Epidemiological Studies Depression scale (CES-D) and Hospital Anxiety and Depression Scale (HADS), 157 (31%) subjects had a WHO Composite International Diagnostic Interview for DSM-IV-disorders by telephone. The GAD-7 had good reliability. Subjects with a GAD-diagnosis had significantly higher means on GAD-2, GAD-SI and GAD-7 than subjects without a GAD-diagnosis. The AUC (Area Under the Curve) of the GAD-SI and GAD-2 was accurate and not significantly different to the GAD-7 AUC. The web-based GAD-SI, GAD-2 and GAD-7 are reliable, valid tools to quickly screen for GAD in busy mental health settings and clinical research. More research is needed to validate the GAD-SI 'Do you have trouble relaxing' to see if its screening properties approach those of the GAD-7.
authors.affiliation: Department of Clinical Psychology, VU University Amsterdam, Amsterdam, The Netherlands. T.Donker@psy.vu.nl
authors.forename: Tara
authors.initials: T
authors.lastname: Donker
authors.forename: Annemieke
authors.initials: A
authors.lastname: van Straten
authors.forename: Isaac
authors.initials: I
authors.lastname: Marks
authors.forename: Pim
authors.initials: P
authors.lastname: Cuijpers
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001008:Anxiety Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology*; D019540:Area Under Curve; D003937:Diagnosis, Differential; D059026:Diagnostic Self Evaluation; D005260:Female; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D012372:ROC Curve; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D055815:Young Adult