title: Performance of administrative case definitions for comorbidity in multiple sclerosis in Manitoba and Nova Scotia.
abstract: BACKGROUND
  As the population ages and the prevalence of comorbid conditions increases, the need for feasible, validated methods of comorbidity surveillance in chronic diseases such as multiple sclerosis (MS) increases.
  
  
  METHODS
  Using kappa (k) statistics, we evaluated the performance of administrative case definitions for comorbidities commonly observed in MS by comparing agreement between Manitoba (MB) administrative data and self-report (n = 606) and Nova Scotia (NS) administrative data and self-report (n = 1923).
  
  
  RESULTS
  Agreement between the administrative definitions and self-report was substantial for hypertension (k = 0.69 [NS], 0.76 [MB]) and diabetes (k = 0.70 [NS], 0.66 [MB]); moderate for hyperlipidemia (k = 0.53 [NS], 0.51 [MB]) and heart disease (k = 0.42 [NS], 0.51 [MB]) and fair for anxiety (k = 0.27 [NS], 0.26 [MB]). In NS, agreement was substantial for inflammatory bowel disease (k = 0.71) and moderate for epilepsy (k = 0.48).
  
  
  CONCLUSIONS
  Administrative definitions for commonly observed comorbidities in MS performed well in 2 distinct jurisdictions. This suggests that they could be used more broadly across Canada and in national studies.
authors.affiliation: Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada; Department of Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: R A
authors.initials: RA
authors.lastname: Marrie
authors.affiliation: Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada; Capital District Health Authority, Halifax, Canada.
authors.forename: J D
authors.initials: JD
authors.lastname: Fisk
authors.affiliation: Capital District Health Authority, Halifax, Canada.
authors.forename: K J
authors.initials: KJ
authors.lastname: Stadnyk
authors.affiliation: Department of Medicine (Neurology), University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: H
authors.initials: H
authors.lastname: Tremlett
authors.affiliation: Department of Epidemiology and Biostatistics and Occupational Health, McGill University, Montréal, Quebec, Canada; Research Institute of the McGill University Health Centre, Montréal, Quebec, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Wolfson
authors.affiliation: Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Warren
authors.affiliation: Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada; Capital District Health Authority, Halifax, Canada.
authors.forename: V
authors.initials: V
authors.lastname: Bhan
authors.affiliation: Department of Internal Medicine, University of Manitoba, Winnipeg, Manitoba, Canada; Department of Community Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: B N
authors.initials: BN
authors.lastname: Yu
mesh_terms: D000328:Adult; D001007:Anxiety / Q000175:diagnosis / Q000453:epidemiology*; D015897:Comorbidity; D016208:Databases, Factual; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology*; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000453:epidemiology*; D004827:Epilepsy / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D006949:Hyperlipidemias / Q000175:diagnosis / Q000453:epidemiology*; D006973:Hypertension / Q000175:diagnosis / Q000453:epidemiology*; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis / Q000453:epidemiology*; D038801:International Classification of Diseases; D008297:Male; D008350:Manitoba / Q000453:epidemiology; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000453:epidemiology*; D009674:Nova Scotia / Q000453:epidemiology; D057566:Self Report