Outcome Measurement, Costing, and Practical Guidance for Evaluating Supported Employment for People with Severe Mental Illness: A Methodological Review

Abstract

Supported employment programs are widely implemented to improve vocational outcomes for people with severe mental illness, yet evaluations of these programs employ highly heterogeneous approaches to costing and outcome measurement. This methodological review examines how costs and outcomes have been identified, measured, and reported in randomized controlled trials of supported employment interventions conducted in high-income countries. Eligible trials were drawn from a recent rapid scoping review and analysed using narrative synthesis, with data extracted on analytical perspectives, outcome domains, costing methods, and data collection approaches. Thirty-two trials were included, of which seven incorporated an economic analysis. Vocational outcomes were consistently prioritised, while clinical, functioning, recovery-oriented, service use, and implementation outcomes were variably assessed. Economic analyses differed substantially in perspective, time horizons, cost identification and valuation, and transparency, limiting comparability and transferability. While methodological diversity reflected differing research questions and policy contexts rather than inconsistent intervention effectiveness, incomplete reporting constrained interpretation and evidence use. Based on these findings, the review outlines practical guidance for evaluators, emphasising alignment of study design with decision making needs, transparent and perspective-consistent costing, theory-informed outcome selection, and explicit documentation of contextual and methodological choices to enhance the policy relevance and interpretability of supported employment evaluations.