SELFIE intervention shows variable cost-effectiveness for youth self-esteem after childhood adversity

BACKGROUND: A novel transdiagnostic blended Ecological Momentary Intervention (EMI) for improving self-esteem in youth who experienced childhood adversity has shown beneficial effects. However, evidence on the cost-effectiveness of SELFIE and EMIs overall is lacking. METHODS: In this RCT-based economic evaluation, participants aged 12-26 years with low self-esteem (<26 on the Rosenberg Self-Esteem Scale [RSES]) and experienced childhood adversity were recruited from specialized mental health services and the general population and randomly allocated to CAU (control condition) or CAU + SELFIE (experimental condition). The Trimbos/iMTA Questionnaire for Costs Associated with Psychiatric Illness (TiC-P), the RSES, and EQ-5D-5L were assessed at baseline, post-intervention, and 6-, 18-, and 24-month follow-up. Incremental cost-effectiveness (ICER) and cost-utility (ICUR) ratios, and acceptability curves, were generated. Sensitivity and subgroup analyses assessed robustness. RESULTS: From a societal perspective, the ICER presented €1,219 per improved point of self-esteem, and the ICUR presented €53,986 per QALY gained. The probability of cost-effectiveness was 26% at a willingness-to-pay (WTP) threshold of €20,000/QALY and 49% at €50,000/QALY. At €50,000/QALY, the probability of cost-effectiveness was 77% from a healthcare perspective (ICUR €15,671/QALY gained) and 87% for participants recruited from specialized mental health services (ICUR €-14,567/QALY gained). CONCLUSIONS: At the societal level, the SELFIE intervention exceeded the WTP threshold. Tests for robustness showed higher probabilities of cost-effectiveness from a healthcare perspective, likely reflecting the absence of educational productivity loss costs in the societal perspective, and in youth recruited from specialized mental health services. The innovative field of blended EMIs yields encouraging first results, urging more cost-effectiveness research.