title: How reliable are national surveillance data? Findings from an audit of Canadian methicillin-resistant Staphylococcus aureus surveillance data.
abstract: BACKGROUND
  The Canadian Nosocomial Infection Surveillance Program (CNISP) has conducted surveillance for incident cases of methicillin-resistant Staphylococcus aureus (MRSA) in sentinel hospitals since 1995. In 2007, a reliability audit of the 2005 data was conducted.
  
  
  METHODS
  In 2005, 5,652 cases were submitted to the CNISP from 43 hospitals. A proportional sample of submitted forms (up to 25) from each site were randomly selected. Stratified random sampling was used to obtain the comparison data. The original data were compared with the reabstracted data for congruence on 7 preselected variables.
  
  
  RESULTS
  Reabstracted data were received from 30 out of 43 hospitals (70%), providing 443 of the 598 case forms requested (74%). Of these, 397 (90%) had matching case identification numbers. Overall, the percentage of discordant responses was 7.0%, ranging from 3.5% for sex and up to 23.7% for less well-defined variables (eg, where MRSA was acquired).
  
  
  CONCLUSIONS
  Our findings suggest that, in general, the 2005 MRSA data are reliable. However to improve reliability a data quality framework with quality assurance practices, including ongoing auditing should be integrated into the CNISP's surveillance programs. Providing training to data collectors and standard definitions with practical examples may help to improve data quality, especially for those variables that require clinical judgment.
authors.affiliation: Powell River General Hospital Quality and Patient Safety, Vancouver Coastal Health Authority, Powell River, BC, Canada.
authors.forename: Leslie
authors.initials: L
authors.lastname: Forrester
authors.forename: Jun Chen
authors.initials: JC
authors.lastname: Collet
authors.forename: Robyn
authors.initials: R
authors.lastname: Mitchell
authors.forename: Linda
authors.initials: L
authors.lastname: Pelude
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Henderson
authors.forename: Joseph
authors.initials: J
authors.lastname: Vayalumkal
authors.forename: Stephanie
authors.initials: S
authors.lastname: Leduc
authors.forename: Saeed
authors.initials: S
authors.lastname: Ghahreman
authors.forename: Christine
authors.initials: C
authors.lastname: Weir
authors.forename: Denise
authors.initials: D
authors.lastname: Gravel
mesh_terms: D002170:Canada / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D003625:Data Collection; D005260:Female; D006761:Hospitals; D006801:Humans; D008297:Male; D008485:Medical Audit; D055624:Methicillin-Resistant Staphylococcus aureus; D011159:Population Surveillance; D015203:Reproducibility of Results; D012107:Research Design; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology