Administrative Database Studies in IBD: A Cautionary Tale

The inflammatory bowel diseases (IBDs) have been extensively studied with administrative databases. Ananthakrishnan et al. (this issue) used an administrative database to develop a risk score that predicted disease severity in hospitalized Crohn's disease patients. To understand the implication of this work, the concept of risk adjustment is reviewed and the advantages and disadvantages of using administrative databases to study hospitalization outcomes in IBD patients are discussed.