Background: Approximately 2 million children are hospitalized each year in the United States, with more than three-quarters of non-elective hospitalizations admitted through emergency departments (EDs). Direct admission, defined as admission to hospital without first receiving care in the hospital’s ED, may offer benefits for patients and healthcare systems in quality, timeliness, and experience of care. While ED utilization patterns are well studied, there is a paucity of research comparing the effectiveness of direct and ED admissions. The overall aim of this project is to compare the effectiveness of a standardized direct admission approach to admission beginning in the ED for hospitalized children.Methods/Design: We will conduct a stepped wedge cluster randomized controlled trial at 3 structurally and geographically diverse hospitals. A total of 70 primary and urgent care practice sites in the hospitals’ catchment areas will be randomized to a time point when they will begin participation in the multi-stakeholder informed direct admission program. This crossover will be unidirectional and occur at 4 time points, six months apart, over a 24-month implementation period. Our primary outcome will be the timeliness of clinical care provision. Secondary outcomes include: (i) parent-reported experience of care; (ii) unanticipated transfer to the intensive care unit within 6 hours of hospital admission; and (iii) rapid response calls within 6 hours of hospital admission. We anticipate that 190 children and adolescents will be directly admitted, with 1506 admitted through EDs. Analyses will compare the effectiveness of direct admission to admission through the ED, and will evaluate the causal effect of implementing a direct admission program using linear regression with random effects for referring practice clusters and time period fixed effects. We will further examine heterogeneity of treatment effects based on hypotheses specified a priori. In addition, we will conduct a mixed-methods process evaluation to assess reach, effectiveness, adoption, implementation and maintenance of our direct admission intervention.Discussion: Our study represents the first randomized controlled trial to compare the effectiveness of direct admission to admission through the ED for pediatric patients. Our scientific approach, pairing a stepped-wedge design with a multi-level assessment of barriers to and facilitators of implementation, will generate valuable data about how positive findings can be reproduced across other healthcare systems.Trial registration: This trial is registered in ClinicalTrials.gov (NCT04192799, registered December 10, 2019, https://clinicaltrials.gov/ct2/show/NCT04192799)