title: Systematic review and meta-analysis of validation studies on a diabetes case definition from health administrative records.
abstract: OBJECTIVE
  Health administrative data are frequently used for diabetes surveillance. We aimed to determine the sensitivity and specificity of a commonly-used diabetes case definition (two physician claims or one hospital discharge abstract record within a two-year period) and their potential effect on prevalence estimation.
  
  
  METHODS
  Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched Medline (from 1950) and Embase (from 1980) databases for validation studies through August 2012 (keywords: "diabetes mellitus"; "administrative databases"; "validation studies"). Reviewers abstracted data with standardized forms and assessed quality using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria. A generalized linear model approach to random-effects bivariate regression meta-analysis was used to pool sensitivity and specificity estimates. We applied correction factors derived from pooled sensitivity and specificity estimates to prevalence estimates from national surveillance reports and projected prevalence estimates over 10 years (to 2018).
  
  
  RESULTS
  The search strategy identified 1423 abstracts among which 11 studies were deemed relevant and reviewed; 6 of these reported sensitivity and specificity allowing pooling in a meta-analysis. Compared to surveys or medical records, sensitivity was 82.3% (95%CI 75.8, 87.4) and specificity was 97.9% (95%CI 96.5, 98.8). The diabetes case definition underestimated prevalence when it was ≤10.6% and overestimated prevalence otherwise.
  
  
  CONCLUSIONS
  The diabetes case definition examined misses up to one fifth of diabetes cases and wrongly identifies diabetes in approximately 2% of the population. This may be sufficiently sensitive and specific for surveillance purposes, in particular monitoring prevalence trends. Applying correction factors to adjust prevalence estimates from this definition may be helpful to increase accuracy of estimates.
authors.affiliation: Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Aaron
authors.initials: A
authors.lastname: Leong
authors.forename: Kaberi
authors.initials: K
authors.lastname: Dasgupta
authors.forename: Sasha
authors.initials: S
authors.lastname: Bernatsky
authors.forename: Diane
authors.initials: D
authors.lastname: Lacaille
authors.forename: Antonio
authors.initials: A
authors.lastname: Avina-Zubieta
authors.forename: Elham
authors.initials: E
authors.lastname: Rahme
mesh_terms: D016208:Databases, Factual; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D016347:Medical Records Systems, Computerized