Clinical, serological and genetic predictors of inflammatory bowel disease course

Table 2 Validation of the positive predictive value of Saint-Antoine predictors

Study	Cohort type	No. of patients	Prevalence of unfavourable course2 (%)	Positive predictive value of the presence of 2 or 3 predictors1 for predicting 5 yr unfavourable clinical course (%)
Reference study
Beaugerie et al[10], 2006	Saint-Antoine referral population	1123	85.2	2 predictors: 91 3 predictors: 93
Validating populations
Beaugerie et al[10], 2006	Independent subsequent sample of the Saint-Antoine referral population	302	85.2	2 predictors: 84 3 predictors: 91
Loly et al[11], 2008	Liege referral population	361	57.9	2 or 3 predictors: 67
Beaugerie et al[62], 2009	Population-based population (Olmstedt county)	423	74.2	2 or 3 predictors: 74

¹Age < 40 years and perianal lesions at first presentation, need for steroids for treating the first flare;

²Unfavourable clinical Crohn’s disease course (one or more of the following criteria: more than 2 steroid courses, steroid dependence, hospitalization for disease flare or complication, disabling chronic symptoms, need for immunosuppressive therapy, intestinal resection or surgical operation for surgical disease) within the 5 years following diagnosis.