Algorithms to identify colonic ischemia, complications of constipation and irritable bowel syndrome in medical claims data: development and validation.
OBJECTIVE
A challenge in the use of insurance claims databases for epidemiologic research is accurate identification and verification of medical conditions. This report describes the development and validation of claims-based algorithms to identify colonic ischemia, hospitalized complications of constipation, and irritable bowel syndrome (IBS).


METHODS
From the research claims databases of a large healthcare company, we selected at random 120 potential cases of IBS and 59 potential cases each of colonic ischemia and hospitalized complications of constipation. We sought the written medical records and were able to abstract 107, 57, and 51 records, respectively. We established a 'true' case status for each subject by applying standard clinical criteria to the available chart data. Comparing the insurance claims histories to the assigned case status, we iteratively developed, tested, and refined claims-based algorithms that would capture the diagnoses obtained from the medical records. We set goals of high specificity for colonic ischemia and hospitalized complications of constipation, and high sensitivity for IBS.


RESULTS
The resulting algorithms substantially improved on the accuracy achievable from a naïve acceptance of the diagnostic codes attached to insurance claims. The specificities for colonic ischemia and serious complications of constipation were 87.2 and 92.7%, respectively, and the sensitivity for IBS was 98.9%.


CONCLUSIONS
U.S. commercial insurance claims data appear to be usable for the study of colonic ischemia, IBS, and serious complications of constipation.
Sands
Bruce E
BE
Gastrointestinal Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA. bsands@partners.org
Duh
Mei-Sheng
MS
Cali
Clorinda
C
Ajene
Anuli
A
Bohn
Rhonda L
RL
Miller
David
D
Cole
J Alexander
JA
Cook
Suzanne F
SF
Walker
Alexander M
AM
D000465:Algorithms; D003106:Colon / Q000098:blood supply*; D003248:Constipation / Q000150:complications*; D003625:Data Collection / Q000379:methods*; D016208:Databases, Factual / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007344:Insurance Claim Reporting; D038801:International Classification of Diseases; D043183:Irritable Bowel Syndrome / Q000453:epidemiology*; D007511:Ischemia / Q000453:epidemiology*