Epidemiology of inflammatory bowel disease

Epidemiology is defined broadly as the study of occurrence of illness. Descriptive epidemiology is the study of disease incidence, prevalence, temporal trends, and demographic factors such as age, gender, and ethnicity. Better understanding of the descriptive epidemiology of IBD (eg, differences in prevalence of IBD based on age or geographic region) may identify areas for further research. This article reviews the descriptive epidemiology of ulcerative colitis and Crohn's disease.