Development and validation of the Nancy histological index for UC.

OBJECTIVE: We developed a validated index for assessing histological disease activity in UC and established its responsiveness. METHODS: Two hundred biopsies were scored. The outcome was the Global Visual Evaluation (GVE). Eight histological features were tested. The Nancy index was developed by multiple linear regression and bootstrap process to create an index that best matched the GVE. Goodness of fit was assessed by the adjusted R squared (adjusted R RESULTS: After backward selection with bootstrap validation, 3/8 items were selected: ulceration (adjusted R CONCLUSIONS: A three descriptor histological index has been validated for use in clinical practice and clinical trials.