Background: Hospitals increasingly deploy integrated, multidisciplinary models, such as clinical pathways, orthogeriatric co-management, hospitalist services, interdisciplinary rounds, and early supported discharge, to improve outcomes and reduce length of stay (LOS). Objective: To synthesize evidence on the effectiveness of integrated, team-based hospital care models on LOS, mortality, readmissions, functional outcomes, complications, and costs. Methods: Following PRISMA guidance, we included randomized and observational studies of adult inpatients receiving integrated multidisciplinary models versus usual care. Outcomes were extracted in duplicate and summarized narratively due to heterogeneity of designs, populations, and interventions; results tables provide study-level details. Results: Eighteen studies were included: nine primary studies in the results set (acute medical, surgical/orthopedic, and stroke care) and nine contextual/systematic reviews for background. Integrated models frequently reduced LOS (hip fracture, heart failure, community-acquired pneumonia, COPD) and, in several settings, lowered mortality or readmissions. Orthogeriatric and hospitalist co-management consistently shortened LOS and accelerated time to surgery in hip fracture cohorts, while clinical pathways and early supported discharge improved efficiency in pneumonia and stroke. Not all models decreased LOS (one stroke rehabilitation trial showed no LOS benefit and faster functional gains with conventional multidisciplinary care). Conclusions: Integrated multidisciplinary hospital care models generally reduce LOS and can improve survival and process outcomes, though effects vary by condition, model design, and implementation fidelity. Standardized reporting and higher-quality comparative trials are needed to define which model features drive benefit.