title: Impact on length of stay after introduction of emergency department information system.
abstract: OBJECTIVE
  An electronic emergency department information system (EDIS) can monitor the progress of a patient visit, facilitate computerized physician order entry, display test results and generate an electronic medical record. Ideally, use of an EDIS will increase overall emergency department (ED) efficiency. However, in academic settings where new interns rotate through the ED monthly, the "learning curve" experienced by the new EDIS user may slow down patient care. In this study, we measured the impact of the "intern learning curve" on patient length of stay (LOS).
  
  
  METHODS
  We retrospectively analyzed one year of patient care data, generated by a comprehensive EDIS in a single, urban, university-affiliated ED. Intern rotations began on the 23rd of each month and ended on the 22nd of the next month. Interns received a 1.5-hour orientation to the EDIS prior to starting their rotation; none had prior experience using the electronic system. Mean LOS (± standard error of the mean) for all patients treated by an intern were calculated for each day of the month. Values for similar numerical days from each month were combined and averaged over the year resulting in 31 discrete mean LOS values. The mean LOS on the first day of the intern rotation was compared with the mean LOS on the last day, using Student's t-test.
  
  
  RESULTS
  During the study period 9,780 patients were cared for by interns; of these, 7,616 (78%) were discharged from the ED and 2,164 (22%) were admitted to the hospital. The mean LOS for all patients on all days was 267 ± 1.8 minutes. There was no difference between the LOS on the first day of the rotation (263±9 minutes) and the last day of the rotation (276 ± 11 minutes, p > 0.9). In a multiple linear regression model, the day of the intern rotation was not associated with patient LOS, even after adjusting for the number of patients treated by interns and total ED census (β = -0.34, p = 0.11).
  
  
  CONCLUSIONS
  In this academic ED, where there is complete intern "turnover" every month, there was no discernible impact of the EDIS "learning curve" on patient LOS.
authors.affiliation: University of Colorado Denver, Division of Emergency Medicine, Aurora, CO.
authors.forename: Paula H
authors.initials: PH
authors.lastname: Mayer
authors.forename: Michael
authors.initials: M
authors.lastname: Yaron
authors.forename: Steven R
authors.initials: SR
authors.lastname: Lowenstein