Endoscopic disease activity indices for ulcerative colitis (UC)
| Endoscopic score | Strengths | Weaknesses |
| Mayo score71 | 4-point scale with the parameters stool frequency, rectal bleeding, endoscopy and physician's global assessment, easy to use even in daily routine. Endoscopic subscore provided (0–3) | Definition of mucosal healing not validated |
| Truelove and Witts score72 | Possibility to stratify patients by their disease severity | No detailed endoscopic analysis, based on the presence of blood in stool rather than the presence of ulcers |
| Baron score73 | 4-point scale, easy to use in daily practice | Lacks assessment of ulcerations, no validation of definition of mucosal healing |
| Modified Baron score74 | 5-point scale, easy to use in daily practice | No validation of definition of mucosal healing |
| Sutherland index75 (ulcerative colitis disease activity index) (modified ulcerative colitis disease activity index) | 4-point scale, easy to use in daily practice | No validation of definition of mucosal healing |
| Powell–Tuck index76 (St Mark's index) | Mainly a clinical measure for stratification of patients | 20-point index with two additional points for a sigmoidoscopy component. Mainly based on clinical parameters rather than endoscopic assessment |
| Rachmilewitz index–endoscopic (clinical activity index; CAI)77 | 12-point index with four components (granulation, vulnerability, vascular pattern, mucosal damage) | Potential underestimation of activity, as even scores in the presence of ulcers may result in the assessment ‘inactive disease’ |
| UCEIS78 | Only validated endoscopic index for UC, accounting for 94% of variance between endoscopists for the overall assessment of severity. Simple scale based on three descriptors, each with 3–4 levels | Responsiveness and clinical relevance need further testing, not used in clinical trials so far |