Background: Greater access to evidence-based psychological treatments is needed. This review aimed to evaluate whether internet-delivered psychological treatments for mood and anxiety disorders are efficacious, noninferior to established treatments, safe, and cost-effective for children, adolescents and adults.
Methods: We searched the literature for studies published until March 2013. Randomized controlled trials (RCTs) were considered for the assessment of short-term efficacy and safety and were pooled in meta-analyses. Other designs were also considered for long-term effect and cost-effectiveness. Comparisons against established treatments were evaluated for noninferiority. Two reviewers independently assessed the relevant studies for risk of bias. The quality of the evidence was graded using an international grading system.
Results: A total of 52 relevant RCTs were identified whereof 12 were excluded due to high risk of bias. Five cost-effectiveness studies were identified and three were excluded due to high risk of bias. The included trials mainly evaluated internet-delivered cognitive behavioral therapy (I-CBT) against a waiting list in adult volunteers and 88% were conducted in Sweden or Australia. One trial involved children. For adults, the quality of evidence was graded as moderate for the short-term efficacy of I-CBT vs. waiting list for mild/moderate depression (d = 0.83; 95% CI 0.59, 1.07) and social phobia (d = 0.85; 95% CI 0.66, 1.05), and moderate for no efficacy of internet-delivered attention bias modification vs. sham treatment for social phobia (d = -0.04; 95% CI -0.24, 0.35). The quality of evidence was graded as low/very low for other disorders, interventions, children/adolescents, noninferiority, adverse events, and cost-effectiveness.
Conclusions: I-CBT is a viable treatment option for adults with depression and some anxiety disorders who request this treatment modality. Important questions remain before broad implementation can be supported. Future research would benefit from prioritizing adapting treatments to children/adolescents and using noninferiority designs with established forms of treatment.