Stress-related mental disorders contribute to work disabilities globally and are a common cause for sick leave. Nature-based rehabilitation (NBR) is a multi-disciplinary approach offered to this patient group on a limited scale. Qualitative studies provide insight into patients' experiences of NBR, and there is a need to synthesize and assess the certainty of evidence for patient-experienced benefits. The aim was to identify, appraise, and synthesize studies reporting experiences and perceived benefits of participation in multidisciplinary, group-based NBR of adult patients with long-standing stress-related mental disorders. PubMed, Embase, CINAHL, AMED, APA PsycInfo, and the Cochrane Library were searched from inception to December 2020. Reference lists of relevant publications were searched. After title and abstract screening, full-text articles were retrieved and assessed for inclusion. The methodological quality of the included studies was assessed, and certainty of evidence was appraised according to CERQual. The search yielded 362 unique records; 19 full-text publications were assessed for eligibility, and 5 studies were included in the synthesis. The studies were considered relevant regarding context, population, and intervention, and quality was generally assessed as moderate to high. Extracted texts were inductively coded and organized into 16 descriptive themes and 4 broad, analytical themes: Instilling calm and joy; Needs being met; Gaining new insights; and Personal growth. Experiences and perceived benefits of participating in NBR and spending time in a nature environment were described as positive for recovery. Nine of the descriptive themes were based on explicit results from at least four of the five studies. Confidence in the evidence of the qualitative findings ranged from moderate to low. Moderate-to-low certainty evidence from the included studies suggests that patients with long-standing stress-related mental disorders experience positive health effects from participating in NBR.
Keywords: nature-based rehabilitation; qualitative; stress-related disorders; synthesis.