title: Hospital discharge abstracts have limited accuracy in identifying occurrence of Clostridium difficile infections among hospitalized individuals with inflammatory bowel disease: A population-based study.
abstract: BACKGROUND
  Hospital discharge databases are used to study the epidemiology of Clostridium difficile infections (CDI) among hospitalized patients with inflammatory bowel disease (IBD). CDI in IBD is increasingly important and accurately estimating its occurrence is critical in understanding its comorbidity. There are limited data on the reliability of the International Classification of Diseases 10th revision (ICD-10) (now widely used in North America) CDI code in determining occurrence of CDI among hospitalized patients. We compared the performance of ICD-10 CDI coding to laboratory confirmed CDI diagnoses.
  
  
  METHODS
  The University of Manitoba IBD Epidemiology Database was used to identify individuals with and without IBD discharged with CDI diagnoses between 07/01/2005 and 3/31/2014. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of ICD-10 CDI code was compared to laboratory CDI diagnoses recorded in a province wide CDI dataset. Multivariable logistic regression models were performed to test the predictors of diagnostic inaccuracy of ICD-10 CDI code.
  
  
  RESULTS
  There were 273 episodes of laboratory confirmed CDI (hospitalized and non-hospitalized) among 7396 individuals with IBD and 536 among 66,297 matched controls. The sensitivity, specificity, PPV and NPV of ICD-10 CDI code in discharge abstracts was 72.8%, 99.6%, 64.1% and 99.7% among those with IBD and 70.8%, 99.9%, 79.0% and 99.9% among those without IBD. Predictors of diagnostic inaccuracy included IBD, older age, increased co-morbidity and earlier years of hospitalization.
  
  
  CONCLUSIONS
  Identification of CDI using ICD-10 CDI code in hospital discharge abstracts may not identify up to 30% of CDI cases, with worse performance among those with IBD.
authors.affiliation: Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.|University of Manitoba IBD Clinical and Research Center, Winnipeg, Manitoba, Canada.|Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Harminder
authors.initials: H
authors.lastname: Singh
authors.affiliation: Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.|University of Manitoba IBD Clinical and Research Center, Winnipeg, Manitoba, Canada.|CancerCare Manitoba, Department of Epidemiology and Cancer Registry, Winnipeg, Manitoba, Canada.
authors.forename: Zoann
authors.initials: Z
authors.lastname: Nugent
authors.affiliation: Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.|Public Health Branch, Manitoba Health, Seniors and Active Living, Winnipeg, Manitoba, Canada.
authors.forename: B Nancy
authors.initials: BN
authors.lastname: Yu
authors.affiliation: Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Lix
authors.affiliation: Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.|University of Manitoba IBD Clinical and Research Center, Winnipeg, Manitoba, Canada.
authors.forename: Laura
authors.initials: L
authors.lastname: Targownik
authors.affiliation: Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.|University of Manitoba IBD Clinical and Research Center, Winnipeg, Manitoba, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Bernstein
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016360:Clostridioides difficile / Q000302:isolation & purification; D003015:Clostridium Infections / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D015897:Comorbidity; D016208:Databases, Factual; D005260:Female; D006760:Hospitalization; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications / Q000453:epidemiology / Q000473:pathology*; D038801:International Classification of Diseases; D016015:Logistic Models; D008875:Middle Aged; D016017:Odds Ratio; D010351:Patient Discharge / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity