Defining a recovery definition and core outcomes of psychosis: protocol of an international Delphi consensus study

Research on recovery after first-episode psychosis remains difficult to compare and synthesise because definitions and outcome measures vary widely, contributing to highly heterogeneous recovery rates (approximately 13.5%-57.0%) and limiting understanding of illness trajectories, determinants of long-term outcomes, and cross-national differences. This perspective describes a protocol for an international Delphi study aiming to establish a clear, operational, and globally applicable definition of recovery after psychosis and to identify a core outcome set for psychosis research. A multidisciplinary steering committee will develop an initial statement framework informed by an umbrella review of recovery definitions, outcomes, and prior consensus-oriented work. We will recruit approximately 60 international panellists, including mental health professionals, and experts with lived experience, with broad representation across regions (North America, Europe, Australia, and the Global South). The Delphi process will include three online rounds, with a minimum retention target of 70% across rounds, and consensus will be determined using prespecified thresholds (consensus ≥75% agreement; emerging consensus 70%-74% with limited dissent; final consensus ≥75% on binary items). Minority positions will be documented and reported. Results will be disseminated via a workshop and peer-reviewed publication to support standardisation of recovery definitions and outcomes and improve comparability and interpretability across psychosis research.