What works in transdiagnostic adult psychiatric day treatment programs? A scoping review of common components contributing to improved mental health outcomes

BACKGROUND: Day Treatment Programs (DTPs) provide intensive, multidisciplinary, non-residential care for adults with acute or complex mental illness. Despite their long-standing role as recovery-oriented alternatives to inpatient admission, contemporary DTPs vary widely in structure and therapeutic orientation. AIMS: To examine differences in transdiagnostic DTP models and review outcome data to inform program development and future research. METHOD: A systematic search across MEDLINE, EMBASE, PsycInfo, and CINAHL databases was conducted. Included studies were mapped by location, design, and program characteristics, then narratively synthesized. RESULTS: The initial search yielded 8820 articles, of which twenty met inclusion criteria. Programs reflected diverse therapeutic orientations, including dialectical behavior therapy, cognitive behavioral therapy, acceptance and commitment therapy, and recovery-based models. Participation in DTPs was associated with reduced psychiatric symptoms, improved functioning, and enhanced quality of life. Common therapeutic factors included structured routines, group-based interventions, milieu therapy, person-centered care, and coordination with community and mental health services. Patient satisfaction was generally high, though concerns regarding continuity of care post-discharge were noted. CONCLUSION: Transdiagnostic DTPs across therapeutic orientations appear effective in promoting recovery in adults with mental illness. However, heterogeneity and limited comparative data hinder conclusions about the relative effectiveness of specific models or other treatment-related factors.