Re-designing emergency medicine physician staffing to augment emergency department capacity: A combined waterfall...

Emergency department (ED) crowding and inpatient boarding delay care and increase the risk of patients leaving without being seen (LWBS). We implemented a combined physician waterfall schedule (PWS) and modified physician-in-triage (PIT) model to expand front-end capacity, accelerate early physician assessment, and reduce LWBS.

We conducted a single-center, retrospective pre-post study of adult ED encounters (≥20 years) over consecutive 12-month pre- and post-intervention periods (January 3, 2023-December 31, 2024). The intervention paired a staggered PWS (increasing attending coverage from 54 to 62 h/day) with a modified PIT model requiring full initial evaluation and clinical ownership through disposition. We used statistical process control (P-chart) to assess monthly LWBS trends and logistic regression with inverse probability of treatment weighting (IPTW) plus covariate adjustment to compare the primary outcome between periods; univariable tests were used for secondary outcomes (throughput, ED returns, and patient experience) and balancing measures (left-before-treatment-complete, ED return within 72-h resulting in hospital admission).

Among 79,898 adult encounters, LWBS decreased from 6.5% to 4.7%. IPTW analysis showed lower odds of LWBS (OR 0.71; 95% CI 0.66-0.76), corresponding to a 28.1% relative reduction and exceeding the 25% target. ED return within 72 h decreased (5.5% to 5.1%, p = 0.004), as did returns with admission (0.8% to 0.7%, p = 0.027). Other secondary outcomes were largely unchanged. Improvements occurred despite increased boarding.

A combined PWS plus modified PIT model was associated with reduced LWBS while maintaining safety and patient experience, offering a pragmatic strategy to mitigate ED crowding.