Cost-effectiveness of Internet-Delivered Emotion Regulation Therapy for Adolescents With Nonsuicidal Self-injury

Objectives: To evaluate the cost-effectiveness of internet-delivered emotion regulation individual therapy for adolescents (IERITA) with nonsuicidal self-injury disorder.Design: Secondary cost-effectiveness analyses from a randomized controlled trial of IERITA plus treatment as usual (TAU) versus TAU only.Setting: Multi-site study at three child and adolescent mental health services in Sweden.Participants: Clinically referred and self-referred adolescent participants meeting diagnostic criteria for nonsuicidal self-injury disorder (N = 166) and their parents. Recruitment took place between November 20, 2017, and April 9, 2020.Interventions: Twelve weeks of IERITA delivered adjunctive to TAU versus TAU only.Main outcomes and measures: Clinical outcomes were frequency of nonsuicidal self-injury (primary outcome) and NSSI remission, assessed by the Deliberate Self-Harm Inventory-Youth version and quality-adjusted life-years (QALYs) estimated based on participant responses on the Kid-Screen 10. Intervention, health care sector, and societal costs were assessed using the parent-rated version of the Trimbos-iMTA questionnaire for costs associated with psychiatric illness. Clinical outcomes and costs were measured before treatment, 1-month post-treatment (primary end-point), and 3-month post-treatment.Results: Adding IERITA to TAU was associated with improved clinical outcomes and increased costs at 1-month post-treatment, reducing one NSSI episode at a cost of $2107 and achieving NSSI remission in one additional participant for $8809. At 3-month post-treatment, IERITA was more effective in clinical outcomes and cost saving from both a societal ($-2067) and health-care perspective ($-425). IERITA had a 48-55% probability of being cost-effective at common QALY willingness-to-pay thresholds at 1-month post-treatment, which increased to 73-76% at the 3-month post-treatment.Conclusions: IERITA delivered adjunctive to TAU is a cost-effective treatment of nonsuicidal self-injury in youth, compared to TAU only. At the 3-month post-treatment assessment, IERITA was associated with both improved clinical outcomes and reduced costs.