Discriminant function analysis to calculate a Crohn's activity group scale to predict future inactive or active disease.

A discriminant function analysis was performed on several demographic, anthropometric, clinical, and laboratory data of 685 observations performed over 12 months on 137 patients with Crohn's disease. A Crohn's activity group scale (CAGS) was calculated. The CAGS has two advantages over the usual Crohn's disease activity index: it is objective, but more important is the fact that the values, when calculated longitudinally, have predictive value. Thus, calculation of CAGS is useful for counseling purposes and may also be useful in the design of future trials assessing therapy for Crohn's disease by allowing prerandomization stratification of patients with high or low probability of future recurrences of symptomatic disease activity.