Identifying disparity in emergency department length of stay and admission likelihood

Background: To assess whether insurance status has an effect on emergency department (ED) length of stay (LOS) and likelihood for admission or transfer to an operating room.

Methods: This was a retrospective cross-sectional study of all encounters from January 2011 through October 2013 at an urban, academic trauma center. Analysis included multi-variable linear regression for ED LOS and logistic regression for the likelihood of admission.

Results: Overall, 201 535 patients met the inclusion criteria, for which the mean age was 43.8 years, 55.9% were female, 23.4% were uninsured and 8% were of non-black race. Admission rate was 24.5% and operative rate was 1.4%. After adjusting for age, sex, triage acuity and race, the presence of insurance coverage was associated with an increased ED LOS of 575 (95%CI 552-598) vs. 567 (95%CI 543-591) minutes (P<0.01) among admitted patients and a decreased ED LOS of 456 (95%CI 381-531) vs. 499 (95%CI 423-575) minutes (P<0.01) among those transferred to an operating room. Adjusting for these same predictors, insured status remained a predictor for admission (odds ratio 1.24, 95%CI 1.20-1.28, P<0.01) and a negative predictor for transfer to the operating room (odds ratio 0.84, 95%CI 0.77-0.92, P<0.01).

Conclusion: The insured experienced a clinically insignificant increase in ED LOS when admitted and a 43-minute decrease in ED LOS when being transferred to the operating room. The insured were more likely to be admitted and less likely to be transferred to an operating room.