THE GREEN ROOM protocol for a mixed-methods study on virtual nature for mental well-being in the acute psychiatry ward

Background Acute psychiatric hospitalization often takes place in highly restrictive environments where patients have limited access to restorative natural settings despite growing evidence that nature exposure benefits psychological well-being. Immersive virtual reality (VR) offers a promising, low-risk approach to providing nature-based experiences within acute psychiatric wards. However, evidence regarding its implementation and effectiveness in routine inpatient psychiatric care remains scarce. Methods THE GREEN ROOM is a single-centre mixed-methods study combining an implementation evaluation with a pragmatic randomized controlled trial. The implementation phase will use semi-structured interviews with patients and healthcare professionals, guided by the Non-adoption, Abandonment, Scale-up, Spread and Sustainability (NASSS) framework, to identify barriers and facilitators to implementation and to inform refinement of the intervention protocol. The second phase consists of a pragmatic, parallel-group randomized controlled trial including 120 psychiatric inpatients, stratified according to voluntary versus involuntary admission status. Participants allocated to the intervention group will receive immersive nature-based VR sessions in addition to treatment as usual. The intervention protocol, including software selection and session characteristics, will be finalized following the implementation phase. Co-primary outcomes are patient satisfaction with hospitalization and perceived stress at discharge. Secondary outcomes include immediate psychological effects of VR, length of hospital stay, discharge against medical advice, and implementation-related outcomes including feasibility, acceptability, usability, recruitment, intervention uptake, and safety. Discussion THE GREEN ROOM will provide evidence regarding both the clinical effectiveness and the real-world implementation of immersive nature-based VR within acute psychiatric inpatient care. By integrating implementation science with a pragmatic randomized controlled trial, this study aims to support the development of scalable and sustainable interventions capable of improving patients’ hospital experience and psychological well-being. Trial registration The study protocol is also registered in the Clinical Trials Registry at ClinicalTrials.gov with the identifier NCT07655063. Date of registration: 12 June 2026.