title: Analyzing Factors Affecting Emergency Department Length of Stay-Using a Competing Risk-accelerated Failure Time Model.
abstract: Emergency department (ED) length of stay (LOS) is associated with ED crowding and related complications. Previous studies either analyzed single patient disposition groups or combined different endpoints as a whole. The aim of this study is to evaluate different effects of relevant factors affecting ED LOS among different patient disposition groups.This is a retrospective electronic data analysis. The ED LOS and relevant covariates of all patients between January 2013 and December 2013 were collected. A competing risk accelerated failure time model was used to compute endpoint type-specific time ratios (TRs) for ED LOS.A total of 149,472 patients was included for analysis with an overall medium ED LOS of 2.15 [interquartile range (IQR) = 6.51] hours. The medium LOS for discharged, admission, and mortality patients was 1.46 (IQR = 2.07), 11.3 (IQR = 33.2), and 7.53 (IQR = 28.0) hours, respectively. In multivariate analysis, age (TR = 1.012, P < 0.0001], higher acuity (triage level I vs level V, TR = 2.371, P < 0.0001), pediatric nontrauma (compared with adult nontrauma, TR = 3.084, P < 0.0001), transferred patients (TR = 2.712, P < 0.0001), and day shift arrival (compared with night shift, TR = 1.451, P < 0.0001) were associated with prolonged ED LOS in the discharged patient group. However, opposite results were noted for higher acuity (triage level I vs level V, TR = 0.532, P < 0.0001), pediatric nontrauma (TR = 0.375, P < 0.0001), transferred patients (TR = 0.852, P < 0.0001), and day shift arrival (TR = 0.88, P < 0.0001) in the admission patient group.Common influential factors such as age, patient entity, triage acuity level, or arrival time may have varying effects on different disposition groups of patients. These findings and the suggested model could be used for EDs to develop individually tailored approaches to minimize ED LOS and further improve ED crowding status.
authors.affiliation: From the Department of Emergency Medicine (C-HC, T-FC, C-JN), Chang Gung Memorial Hospital, Linkou and Chang Gung University College of Medicine, Taoyuan, Taiwan; Institute of Epidemiology and Preventive Medicine (C-HC, H-HC), College of Public Health, National Taiwan University, Taipei, Taiwan; and School of Oral Hygiene (AM-FY), College of Oral Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chung-Hsien
authors.initials: CH
authors.lastname: Chaou
authors.forename: Te-Fa
authors.initials: TF
authors.lastname: Chiu
authors.forename: Amy Ming-Fang
authors.initials: AM
authors.lastname: Yen
authors.forename: Chip-Jin
authors.initials: CJ
authors.lastname: Ng
authors.forename: Hsiu-Hsi
authors.initials: HH
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D012189:Retrospective Studies; D012306:Risk; D013997:Time Factors; D055815:Young Adult