Optimising a complex intervention for youth mental health using multi-criteria decision analysis

Introduction

Majority of adolescents live in more restricted resource settings with additional socioeconomic stressors, adverse childhood experiences, and limited mental health services access. The FLOURISH (Family-Focused Adolescent & Lifelong Health Promotion) project adapts, implements, and evaluates a parenting intervention for adolescent mental health promotion in North Macedonia and Moldova. We used a new multi-criteria decision analysis (MCDA) approach to assess intervention component combinations for optimised delivery.

Methods

In a factorial cluster trial, adolescents (10-14 years) and caregivers received the Parenting for Lifelong Health (PLH) Teens intervention with 3 randomized add-on components for mental health (HAT), peer support and engagement in 2025. Conceptual model-based outcome data were collected at baseline and follow-up alongside detailed cost information. A 6-step MCDA framework was used for optimisation. Evaluation criteria, measures and weights reflecting joint outcomes were defined by formal stakeholder elicitation process. Change scores were analysed using multi-level regression and valued as cost per combined benefit score (CBS).

Results

We assessed eight component combinations against seven outcomes for 640 families. Core PLH cost €162 per family and yielded a CBS of 42 (€3.86 per CBS). PLH+HAT was most effective with a CBS of 75 at €248 per family (€2.63 per CBS). It dominated all two or three add-on combinations, and was of better value than other single add-on combinations. Compared to PLH, PLH+HAT had more heterogeneous impacts across outcomes.

Discussion

MCDA successfully informed optimised component selection for a complex youth mental health promotion intervention in restricted resource settings. PLH only and PLH+HAT combinations both yielded similar incremental cost per CBS. Additional qualitative information indicated further optimisation needs for HAT with PLH only considered for further implementation.

Key messages

• Adolescent mental health promotion requires effective, cost-effective and scalable interventions, especially in more resource restricted settings, as investigated in FLOURISH.

• Multi-criteria decision analysis proved to be a viable and helpful tool to optimise complex parenting interventions for further implementation.