Comparing administrative and survey data for ascertaining cases of irritable bowel syndrome: a population-based investigation
1 School of Public Health, University of Saskatchewan, Saskatoon, Canada
2 Manitoba Centre for Health Policy, University of Manitoba, Winnipeg, Canada
3 Department of Community Health Sciences, University of Manitoba, Winnipeg, Canada
4 Section of Gastroenterology, Department of Internal Medicine, University of Manitoba, Winnipeg, Canada
5 College of Medicine, University of Saskatchewan, Saskatoon, Canada
6 Department of Mathematics and Statistics, University of Saskatchewan, Saskatoon, Canada
BMC Health Services Research 2010, 10:31 doi:10.1186/1472-6963-10-31Published: 1 February 2010
Administrative and survey data are two key data sources for population-based research about chronic disease. The objectives of this methodological paper are to: (1) estimate agreement between the two data sources for irritable bowel syndrome (IBS) and compare the results to those for inflammatory bowel disease (IBD); (2) compare the frequency of IBS-related diagnoses in administrative data for survey respondents with and without self-reported IBS, and (3) estimate IBS prevalence from both sources.
This retrospective cohort study used linked administrative and health survey data for 5,134 adults from the province of Manitoba, Canada. Diagnoses in hospital and physician administrative data were investigated for respondents with self-reported IBS, IBD, and no bowel disorder. Agreement between survey and administrative data was estimated using the κ statistic. The χ2 statistic tested the association between the frequency of IBS-related diagnoses and self-reported IBS. Crude, sex-specific, and age-specific IBS prevalence estimates were calculated from both sources.
Overall, 3.0% of the cohort had self-reported IBS, 0.8% had self-reported IBD, and 95.3% reported no bowel disorder. Agreement was poor to fair for IBS and substantially higher for IBD. The most frequent IBS-related diagnoses among the cohort were anxiety disorders (34.4%), symptoms of the abdomen and pelvis (26.9%), and diverticulitis of the intestine (10.6%). Crude IBS prevalence estimates from both sources were lower than those reported previously.
Poor agreement between administrative and survey data for IBS may account for differences in the results of health services and outcomes research using these sources. Further research is needed to identify the optimal method(s) to ascertain IBS cases in both data sources.