Psychological treatment of generalized anxiety disorder: a meta-analysis.
Recent years have seen a near-doubling of the number of studies examining the effects of psychotherapies for generalized anxiety disorder (GAD) in adults. The present article integrates this new evidence with the older literature through a quantitative meta-analysis. A total of 41 studies (with 2132 patients meeting diagnostic criteria for GAD) were identified through systematic searches in bibliographical databases, and were included in the meta-analysis. Most studies examined the effects of cognitive behavior therapy (CBT). The majority of studies used waiting lists as control condition. The pooled effect of the 38 comparisons (from 28 studies) of psychotherapy versus a control group was large (g=0.84; 95% CI: 0.71-0.97) with low to moderate heterogeneity. The effects based on self-report measures were somewhat lower than those based on clinician-rated instruments. The effects on depression were also large (g=0.71; 95% CI: 0.59-0.82). There were some indications for publication bias. The number of studies comparing CBT with other psychotherapies (e.g., applied relaxation) or pharmacotherapy was too small to draw conclusions about comparative effectiveness or the long-term effects. There were some indications that CBT was also effective at follow-up and that CBT was more effective than applied relaxation in the longer term.
Department of Clinical Psychology, VU University Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, The Netherlands; Leuphana University, Innovation Incubator, Division Health Trainings Online, Lueneburg, Germany. Electronic address: p.cuijpers@vu.nl.
Pim
P
Cuijpers
Department of Clinical Psychology, VU University Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, The Netherlands.
Marit
M
Sijbrandij
Department of Clinical Psychology, VU University Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, The Netherlands.
Sander
S
Koole
Department of Clinical Psychology, VU University Amsterdam, The Netherlands; EMGO Institute for Health and Care Research, The Netherlands.
Marcus
M
Huibers
Leuphana University, Innovation Incubator, Division Health Trainings Online, Lueneburg, Germany; Philipps-University Marburg, Germany.
Matthias
M
Berking
Department of Behavioural Sciences and Learning, Linköping University, Sweden; Department of Clinical Neuroscience, Psychiatry Section, Karolinska Institutet, Stockholm, Sweden.
Gerhard
G
Andersson
D001008:Anxiety Disorders / Q000523:psychology / Q000628:therapy*; D015928:Cognitive Behavioral Therapy; D006801:Humans; D012064:Relaxation Therapy; D016896:Treatment Outcome
Cognitive behavior therapy; Comparative outcome studies; Generalized anxiety disorder; Meta-analysis; Psychotherapy; Randomized trial