National Study of Patient, Visit, and Hospital Characteristics Associated With Leaving an Emergency Department Without Being Seen: Predicting LWBS

OBJECTIVES: The objective was to estimate the national left-without-being-seen (LWBS) rate and to identify patient, visit, and institutional characteristics that predict LWBS. METHODS: This was a retrospective cross-sectional analysis using the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 1998 to 2006. Bivariate and multivariate analyses were performed to identify predictors of LWBS. RESULTS: The national LWBS rate was 1.7 (95% confidence interval [CI] = 1.6 to 1.9) patients per 100 emergency department (ED) visits each year. In multivariate analysis, patients at extremes of age (<18 years, odds ratio [OR] = 0.80, 95% CI = 0.66 to 0.96; and > or =65 years, OR = 0.46, 95% CI = 0.32 to 0.64) and nursing home residents (OR = 0.29, 95% CI = 0.08 to 1.00) were associated with lower LWBS rates. Nonwhites (black or African American (OR = 1.41, 95% CI = 1.22 to 1.63) and Hispanic (OR = 1.25, 95% CI = 1.04 to 1.49), Medicaid (OR = 1.47, 95% CI = 1.27 to 1.70), self-pay (OR = 1.96, 95% CI = 1.65 to 2.32), or other insurance (OR = 2.09, 95% CI = 1.74 to 2.52) patients were more likely to LWBS. Visit characteristics associated with LWBS included visits for musculoskeletal (OR = 0.70, 95% CI = 0.57 to 0.85), injury/poisoning/adverse event (OR = 0.65, 95% CI = 0.53 to 0.80), and miscellaneous (OR = 1.56, 95% CI = 1.19 to 2.05) complaints. Visits with low triage acuity were more likely to LWBS (OR = 3.59, 95% CI = 2.81 to 4.58), whereas visits that were work-related were less likely to LWBS (OR = 0.19, 95% CI = 0.12 to 0.29). Institutional characteristics associated with LWBS were visits in metropolitan areas (OR = 2.11, 95% CI = 1.66 to 2.70) and teaching institutions (OR = 1.33, 95% CI = 1.06 to 1.67). CONCLUSIONS: Several patient, visit, and hospital characteristics are independently associated with LWBS. Prediction and benchmarking of LWBS rates should adjust for these factors.