Validation of international algorithms to identify adults with inflammatory bowel disease in health administrative data from Ontario, Canada.
OBJECTIVE
Health administrative databases can be used to track disease incidence, outcomes, and care quality. Case validation is necessary to ensure accurate disease ascertainment using these databases. In this study, we aimed to validate adult-onset inflammatory bowel disease (IBD) identification algorithms.


METHODS
We used two large cohorts of incident patients from Ontario, Canada to validate algorithms. We linked information extracted from charts to health administrative data and compared the accuracy of various algorithms. In addition, we validated an algorithm to distinguish patients with Crohn's from those with ulcerative colitis and assessed the adequate look-back period to distinguish incident from prevalent cases.


RESULTS
Over 5,000 algorithms were tested. The most accurate algorithm to identify patients 18 to 64 years at diagnosis was five physician contacts or hospitalizations within 4 years (sensitivity, 76.8%; specificity, 96.2%; positive predictive value (PPV), 81.4%; negative predictive value (NPV), 95.0%). In patients ≥65 years at diagnosis, adding a pharmacy claim for an IBD-related medication improved accuracy.


CONCLUSIONS
Patients with adult-onset incident IBD can be accurately identified from within health administrative data. The validated algorithms will be applied to administrative data to expand the Ontario Crohn's and Colitis Cohort to all patients with IBD in the province of Ontario.
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, Ontario, Canada, M4N 3M5; CHEO Inflammatory Bowel Disease Centre, Division of Gastroenterology, Hepatology and Nutrition, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, Ontario, Canada K1H 8L1; Department of Pediatrics, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada, K1H 8M5; Department of Epidemiology and Community Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada, K1H 8M5. Electronic address: ebenchimol@cheo.on.ca.
Eric I
EI
Benchimol
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, Ontario, Canada, M4N 3M5; Department of Paediatrics, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8; Institute of Health Policy, Management and Evaluation, 155 College Street, University of Toronto, Toronto, Ontario, Canada, M5T 3M7.
Astrid
A
Guttmann
CHEO Inflammatory Bowel Disease Centre, Division of Gastroenterology, Hepatology and Nutrition, Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, Ontario, Canada K1H 8L1; Department of Pediatrics, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada, K1H 8M5.
David R
DR
Mack
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, Ontario, Canada, M4N 3M5; Department of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada, M5S 1A8; Centre for Inflammatory Bowel Disease, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario, Canada, M5G 1X5.
Geoffrey C
GC
Nguyen
Department of Medicine, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada, L8S 4K1.
John K
JK
Marshall
Department of Medicine, London Health Sciences Centre, University of Western Ontario, 339 Windermere Road, London, Ontario, Canada, N6G 2V4.
James C
JC
Gregor
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, Ontario, Canada, M4N 3M5.
Jenna
J
Wong
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, Ontario, Canada, M4N 3M5; Department of Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada, K1H 8M5; Ottawa Hospital Research Institute, 725 Parkdale Ave., Ottawa, Ontario, Canada, K1Y 4E9.
Alan J
AJ
Forster
Institute for Clinical Evaluative Sciences, 2075 Bayview Avenue, Toronto, Ontario, Canada, M4N 3M5; Department of Epidemiology and Community Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada, K1H 8M5; Ottawa Hospital Research Institute, 725 Parkdale Ave., Ottawa, Ontario, Canada, K1Y 4E9; Department of Family Medicine, University of Ottawa, 451 Smyth Road, Ottawa, Ontario, Canada, K1H 8M5.
Douglas G
DG
Manuel
D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000453:epidemiology*; D003424:Crohn Disease / Q000175:diagnosis / Q000453:epidemiology*; D057225:Data Mining; D016208:Databases, Factual; D003937:Diagnosis, Differential; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D016347:Medical Records Systems, Computerized; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D015995:Prevalence; D015203:Reproducibility of Results; D055815:Young Adult
Crohn's; Epidemiology; Health administrative data; Inflammatory bowel disease; Routinely collected health data; Ulcerative colitis; Validation