Abstract
Background: Paediatric anxiety disorders are prevalent and associated with substantial disability and long-term adverse consequences. Only a minority of affected children have access to evidence-based treatment; internet-delivered cognitive behaviour therapy (ICBT) could help increase accessibility but needs further rigorous evaluation. The objective of this trial was to evaluate the clinical efficacy and cost-effectiveness of ICBT in the treatment of paediatric anxiety disorders.
Methods: In this single-blind randomised controlled trial, children 8-12 years with a principal anxiety disorder diagnosis were randomly allocated (1:1) to ICBT or internet-delivered child-directed play (ICDP), an active comparator aimed to improve parent-child relationships and increase child self-esteem without directly targeting anxiety. The study was conducted at a single site within the Stockholm specialist child and adolescent mental health services (CAMHS). Primary endpoint was clinician-rated symptom severity (CSR) of the principal anxiety disorder at post-treatment. All participants were included in the primary analysis (intent-to-treat). Trial registration number: NCT02350257.
Findings: Participants (N=131) were recruited between March 2015 and October 2016, mainly via advertisement and referrals from CAMHS, and allocated to ICBT (n=66) or ICDP (n=65). Analyses revealed greater reduction of symptom severity in favour of ICBT (mean difference 0·79, 95% CI 0·42 to 1·16, p=0·002; Cohen’s d=0·77, 95% CI 0·40 to 1·15) and at post-treatment, 48% (n=29) of participants randomised to ICBT no longer fulfilled their principal diagnosis, compared to 15% (n=9) in ICDP (odds ratio 5·41, 95% CI 2·26 to 12·90, p<0·0001). Numbers needed to treat were 3 (95% CI 2·85 to 3·15). Treatment gains were maintained at 3-month follow-up, at which point 70% (n=40) of participants randomised to ICBT no longer met the criteria for their principal anxiety disorder. ICBT resulted in an average societal cost saving of €493·05 (95% CI 477·17 to 508·92) per participant. No severe adverse events were reported.
Interpretation: ICBT is a cost-effective treatment for paediatric anxiety disorders that should be considered for implementation in routine clinical care.
