A mixed-methods study to evaluate the feasibility and preliminary efficacy of delivering the optimal health program (OHP) for youth at clinical high risk (CHR) for psychosis: A study protocol.

Individuals with clinical high risk (CHR) for psychosis experience significant distress, impaired general functioning and a high lifetime risk of self-harm and attempted suicide. The CHR period is an important phase in an individual's mental health where appropriate interventions may reduce the risk of progression to several negative outcomes, including the development of schizophrenia. Given that up to 80% of individuals with CHR have another diagnosable mental illness and almost half experience poor psychosocial functioning, developing interventions that address psychosocial functioning in young people with CHR is of great importance. This mixed-methods study aims to employ qualitative and quantitative methods to adapt an evidence-based comprehensive psychosocial and mental health self-efficacy program, the Optimal Health Program (OHP), and evaluate the feasibility, acceptability and preliminary clinical efficacy in young people with CHR. We aim to recruit 30 CHR participants (age 16-29 years) in a single-arm 12-week exploratory clinical trial. Feasibility metrics will include recruitment, retention, and data completion rates. Acceptability will be informed by the Client Satisfaction Questionnaire. Clinical assessments (psychosis spectrum symptoms, depression, and anxiety), functional measures, and cognitive outcomes will be completed at study entry and repeated post-intervention at 12-weeks. We will run pre-post test data analysis to examine changes following engagement in the OHP intervention. Qualitative interviews will be conducted post-intervention to further evaluate the acceptability of the intervention and the trial design, and will be analyzed using thematic analysis. OHP may enhance the long-term mental health, well-being and functioning of CHR youth. However, the intervention must first be adapted to a CHR population; then, the feasibility and preliminary efficacy of delivering an intervention tailored around the varied needs of the CHR group must be established before a larger-scale appropriately powered study is pursued. Trial registration: The trial is registered with ClinicalTrials.gov NCT05757128.