Economic Evaluations of Internet-Based Psychological Interventions for Anxiety Disorders and Depression: A Systematic Review.

Abstract Background Internet-based interventions show clinical effectiveness for treating anxiety disorders and depression and could make mental healthcare more affordable. Methods We searched databases including PubMed; EMBASE; Cochrane Central; PsychINFO; CINAHL; EconLit; and Web of Science from January 1, 2000 to August 21, 2020. Inclusion criteria were: 1) pertained to the treatment or prevention of anxiety disorders or depression; 2) evaluated the use of an internet-delivered psychological intervention; 3) recruited participants; and 4) reported costs or cost-effectiveness. Results Of the 6,069 articles identified, 33 targeted anxiety (N=13) and depression (n=20) and met final inclusion criteria. All studies were from high-income countries. The control conditions and cost components included were heterogeneous. Only eight studies reported costs of developing the intervention. Of 27 studies that made a conclusion about cost-effectiveness, 81% of interventions were cost-effective. The quality of studies included was high based on a quality assessment checklist of economic evaluations, although many studies did not include definitions of cost components or differentiate between patient-side and system-level costs. Limitations Studies varied in methodology, making conclusions about cost-effectiveness difficult. The generalizability of these results is unclear as studies were clustered in a small number of high-income countries and costs vary over time and between regions. Conclusions Internet-delivered interventions appeared to be cost-effective although control conditions and cost component reporting were variable. We propose a checklist of cost components for future cost analyses to better compare intervention costs. More research is needed to describe development costs, cost-effectiveness in low-resource settings, and cost-effectiveness of newer technologies.