title: Pediatric abdominal radiograph use, constipation, and significant misdiagnoses.
abstract: OBJECTIVE
  To determine the proportion of children diagnosed with constipation assigned a significant alternative diagnosis within 7 days (misdiagnosis), if there is an association between abdominal radiograph (AXR) performance and misdiagnosis, and features that might identify children with misdiagnoses.
  
  
  METHODS
  We conducted a retrospective cohort study of consecutive children <18 years who presented to a pediatric emergency department in Toronto, between 2008 and 2010. Children assigned an International Statistical Classification of Diseases and Related Health Problems 10th Revision code consistent with constipation were eligible. Misdiagnosis was defined as an alternative diagnosis during the subsequent 7 days that resulted in hospitalization or an outpatient procedure that included a surgical or radiologic intervention. Constipation severity was classified employing text word categorization and the Leech score.
  
  
  RESULTS
  3685 eligible visits were identified. Mean age was 6.6 ± 4.4 years. AXR was performed in 46% (1693/3685). Twenty misdiagnoses (0.5%; 95% CI 0.4, 0.8) were identified (appendicitis [7%], intussusception [2%, bowel obstruction [2%], other [9%]). AXR was performed more frequently in misdiagnosed children (75% vs 46%; P = .01). These children more often had abdominal pain (70% vs 49%; P = .04) and tenderness (60% vs 32%; P =.01). Children in both groups had similar amounts of stool on AXR (P = .38) and mean Leech scores (misdiagnosed = 7.9 ± 3.4; not misdiagnosed = 7.7 ± 2.9; P = .85).
  
  
  CONCLUSIONS
  Misdiagnoses in children with constipation are more frequent in those in whom an AXR was performed and those with abdominal pain and tenderness. The performance of an AXR may indicate diagnostic uncertainty; in such cases, the presence of stool on AXR does not rule out an alternative diagnosis.
authors.affiliation: Divisions of Pediatric Emergency Medicine and Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, The Hospital for Sick Children, and Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Faculty of Medicine, University of Toronto, Toronto, ON. Electronic address: stephen.freedman@albertahealthservices.ca.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Freedman
authors.affiliation: Division of Pediatric Emergency Medicine, Department of Pediatrics, The Hospital for Sick Children, Faculty of Medicine, University of Toronto, Toronto, ON.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Thull-Freedman
authors.affiliation: Department of Diagnostic Imaging, Hospital for Sick Children, Division of Pediatric Imaging, Department of Medical Imaging, University of Toronto, Toronto, ON.
authors.forename: David
authors.initials: D
authors.lastname: Manson
authors.affiliation: Division of Pediatric Emergency Medicine, The Hospital for Sick Children, Toronto, ON.
authors.forename: Margot Follett
authors.initials: MF
authors.lastname: Rowe
authors.affiliation: Division of Pediatric Emergency Medicine, Department of Pediatrics, The Hospital for Sick Children, Faculty of Medicine, University of Toronto, Toronto, ON.
authors.forename: Maggie
authors.initials: M
authors.lastname: Rumantir
authors.affiliation: Department of Pediatrics, The Hospital for Sick Children, Faculty of Medicine, University of Toronto, Toronto, ON.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Eltorki
authors.affiliation: Division of Pediatric Emergency Medicine, Department of Pediatrics, The Hospital for Sick Children, and Child Health Evaluative Sciences, The Hospital for Sick Children Research Institute, Faculty of Medicine, University of Toronto, Toronto, ON.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Schuh
mesh_terms: D015746:Abdominal Pain / Q000000981:diagnostic imaging / Q000209:etiology*; D002648:Child; D003248:Constipation / Q000150:complications / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011860:Radiography, Abdominal / Q000379:methods* / Q000706:statistics & numerical data; D012189:Retrospective Studies
keywords: AXR; Abdominal radiograph; ED; Emergency department