COST-EFFECTIVENESS OF GUIDED INTERNET-BASED TREATMENTS FOR DEPRESSION IN COMPARISON WITH CONTROL CONDITIONS: AN INDIVIDUAL PARTICIPANT DATA META-ANALYSIS

Objectives: Previous studies have shown the effectiveness of guided Internetbasedinterventions for depression compared to control groups. It is often hypothesizedthat Internet-based treatments are associated with lower costs, becauseface-to-face time with therapist is reduced. The objective of this study was toconduct an individual-participant data meta-analysis (IPD-MA) evaluating the costeffectivenessof guided Internet-based interventions for depression compared tocontrols from a societal perspective. Methods: A systematic literature searchwas conducted in electronic databases from 2000 to January 1st 2017. Studieswere included if they were randomized controlled trials (RCTs) in which the costeffectivenessof a guided Internet-based intervention for depression was comparedto a control. Cost-effectiveness analyses were conducted for improvement in depressivesymptoms measured by CES-D, response to treatment, and Quality-AdjustedLife-Years (QALYs) at 8-weeks, 6-months, and 12-months follow-up. Results: IPD from five studies, including 1,426 participants were used. The guided Internet-basedinterventions were more costly than the controls, but not statistically significantlyso (e.g.12-months mean difference = € 406, 95%CI: -611 to 1,444). Cost-effectivenessacceptability curves indicated that high investments are needed to reach an acceptableprobability that the intervention is cost-effective compared to control for CES-Dand response to treatment (e.g., at 12-month follow-up the probability of being costeffectivewas 0.95 at a ceiling ratio of 2,000 € /point of improvement in CES-D score).For QALYs, the intervention’s probability of being cost-effective compared to controlwas low at the commonly accepted willingness-to-pay threshold (e.g., at 12-monthfollow-up the probability was 0.29 and 0.31 at a ceiling ratio of 24,000 and 35,000€ /QALY, respectively). Conclusions: Guided Internet-based interventions fordepression were not considered cost-effective compared to control. However, onlya minority of RCTs investigating the clinical effectiveness of guided Internet-basedinterventions also assessed cost-effectiveness. Therefore, it is important that futureRCTs measure resource use and productivity losses alongside clinical effectiveness.