Can simplified endoscopic score for Crohn’s disease be simpler? --Development and Validation of the Multimodal Activity Score for Crohn's Disease (MAS-CD)

Abstract Background Endoscopy is central to diagnosing and monitoring Crohn’s disease (CD), but current endoscopic scoring systems such as the Simplified Endoscopic Score for Crohn’s Disease (SES-CD) are complex, time-consuming, and limited when ileocolonoscopy is incomplete. Approximately 30–40% of CD patients cannot undergo full examinations, hindering comprehensive assessment. With mucosal healing now a key therapeutic target, there is an urgent need for a simpler, multimodal, and clinically practical scoring tool. Objectives To develop and prospectively validate a novel comprehensive assessment tool—the Multimodal Activity Score for Crohn’s Disease (MAS-CD)—that combines endoscopic and, when necessary, radiological parameters.