Background: Childhood and adolescent anxiety disorders are relatively common, occurring in between 5-18% of all children and adolescents. They are associated with significant morbidity and impairment in social and academic functioning, and when persistent, there is a risk of depression, suicide attempts and substance abuse in adulthood. There is accumulating evidence for the efficacy of cognitive behavioural therapy (CBT), with a number of randomised controlled trials (RCTs) suggesting benefit.
Objectives: To determine whether CBT is an effective treatment for childhood and adolescent anxiety disorders in comparison to waiting list or attention controls.
Search strategy: Search of the Cochrane Register of Controlled Trials and the Cochrane Depression, Anxiety and Neurosis Group Register, which includes relevant randomised controlled trials from the bibliographic databases - The Cochrane Library ( to January 2004), EMBASE, (1970-2004) MEDLINE (1970-2004) and PsycINFO (1970-2004). We also searched the references of all included studies and relevant textbooks, and contacted authors in order to identify further trials.
Selection criteria: . Each identified study was assessed for possible inclusion by two reviewers independently. Inclusion criteria consisted of randomised controlled trials of CBT versus waiting list/attention controls in children (more than six years of age) and adolescents (under the age of 19 years) with a DSM (Diagnostic Statistical Manual) or ICD (International Classification of Diseases) anxiety diagnosis; and excluding simple phobia, obsessive compulsive disorder and post-traumatic stress disorder. Each study was required to conform to the principles of CBT through use of a protocol and comprising at least eight sessions of CBT.
Data collection and analysis: The methodological quality of included trials was assessed by two reviewers independently. The dichotomous outcome of remission of anxiety diagnosis was pooled using relative risk (RR) with 95% confidence intervals. Means and standard deviations of anxiety symptom continuous scores were pooled using the standardised mean difference (SMD). Heterogeneity was assessed and intention-to-treat (ITT) analyses undertaken. The presence of publication bias was assessed using funnel plots.
Main results: Thirteen studies with 498 subjects and 311 controls met the inclusion criteria and were included in the analyses. The studies involved community or outpatient subjects only, with anxiety of only mild to moderate severity. ITT analyses showed a response rate for remission of any anxiety diagnosis of 56% for CBT versus 28.2% for controls (RR 0.61,95%CI 0.53 to 0.69), with no evidence of heterogeneity. The number needed to treat (NNT) was 3.0 (95%CI 2.5 to 4.5). For reduction in anxiety symptoms, the SMD was -0.58 (95% CI 0.76 to -0.40) with no significant heterogeneity indicated. Individual, group and family/parental formats of CBT produced fairly similar outcomes.
Authors' conclusions: Cognitive behavioural therapy appears an effective treatment for childhood and adolescent anxiety disorders in comparison to waiting list or attention control. There was no evidence for a difference between an individual, group or parental/family format. CBT can be recommended for the treatment of childhood and anxiety disorders, although with only just over half improving, there is a need for further therapeutic developments.