title: Markers of overcrowding in a pediatric emergency department.
abstract: OBJECTIVE
  The objective of this study was to identify markers of overcrowding in pediatric emergency departments (PEDs) according to expert opinion and then to use statistical methods to further explore the underlying construct of overcrowding.
  
  
  METHODS
  A cross-sectional survey of all PED directors (n = 12) and pediatric emergency medicine fellowship program directors (n = 10) across Canada was conducted to elicit expert opinion on relevant markers of emergency department (ED) crowding. The list of markers was reduced to those specific to the ED for which data could be extracted from one tertiary care PED from an existing computerized patient tracking system. Data representing 2,190 consecutive shifts and 138,361 patient visits were collected between April 2005 and March 2007. Common factor analysis (CFA) was used to determine the underlying factors that best represented overcrowding as determined by markers identified by experts in pediatric emergency medicine
  
  
  RESULTS
  The main markers of overcrowding identified by the survey included measures of patient volume (25%), ED operational processes (55%), and delays in transferring patients to inpatient beds (13%). Data collected on 41 markers were retained for the CFA. The results of the CFA indicated that the largest portion of variation in the data (48%) was accounted for by markers describing patient volumes and flow through the ED. Measures of admission delays accounted for a smaller proportion of variability (9%).
  
  
  CONCLUSIONS
  The results suggest that for this tertiary PED, markers of ED operational processes and patient volume may be more relevant for determination of overcrowding than markers reflecting delays in transferring patients to inpatient beds. This study provides a foundation for further research on markers of overcrowding specific to the pediatric setting.
authors.affiliation: Pediatric Emergency Department, Montreal Children's Hospital, McGill University, Montreal, Quebec, Canada. antonia.stang@albertahealthservices.ca
authors.forename: Antonia S
authors.initials: AS
authors.lastname: Stang
authors.forename: David
authors.initials: D
authors.lastname: McGillivray
authors.forename: Maala
authors.initials: M
authors.lastname: Bhatt
authors.forename: Antoinette
authors.initials: A
authors.lastname: Colacone
authors.forename: Nathalie
authors.initials: N
authors.lastname: Soucy
authors.forename: Ruth
authors.initials: R
authors.lastname: Léger
authors.forename: Marc
authors.initials: M
authors.lastname: Afilalo
mesh_terms: D002170:Canada; D003430:Cross-Sectional Studies; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005163:Factor Analysis, Statistical; D006801:Humans; D009874:Operations Research; D010360:Patient Transfer / Q000706:statistics & numerical data; D010361:Patients / Q000706:statistics & numerical data*; D010372:Pediatrics / Q000458:organization & administration; D017064:Process Assessment, Health Care; D014218:Triage / Q000706:statistics & numerical data