ObjectivesThe objective was to derive and validate a novel queuing theory–based model that predicts the effect of various patient crowding scenarios on patient left without being seen (LWBS) rates.MethodsRetrospective data were collected from all patient presentations to triage at an urban,...

Emergency department (ED) crowding is an international phenomenon that continues to challenge operational efficiency. Many statistical modeling approaches have been offered to describe, and at times predict, ED patient load and crowding. A number of formula-based equations, regression models,...