The clinical Mayo Score or partial Mayo Score (PMS), uses the three non-invasive components of the full Mayo Score (stool frequency, rectal bleeding and Physician’s global assessment). This excludes the score for the endoscopic findings, therefore the maximum score is reduced from 12 to 9 points (1,2).
This simplified index maintains a good relationship with the full Mayo Score in identifying clinical response as perceived by patients (3).
The index considers three clinical parameters, each of which is assigned a score from 0 to 3 according to the clinical evaluation.

Parameter Clinical evaluation (single choice) Score
1. Stool frequency
(per day)
  • normal number of stools
  • 1-2 more than normal
  • 3-4 more than normal
  • ≥ 5 more than normal
2. Rectal bleeding
(indicate the most severe bleeding of the day)
  • none
  • streaks of blood with stool in less than half of the cases
  • obvious blood with stools in most cases
  • blood alone passes
3. Physician’s global assessment
  • normal
  • mild disease
  • moderate disease
  • severe disease

Calculation formula: sum of the scores the three parameters.
Clinical response is defined as a decrease of at least 2 points of the Mayo Clinical Score (4).

Decoding table (1)

Score Decoding
< 2 remission
2 - 4 mild activity
5 - 7 moderate activity
> 7 severe activity
  • Schroeder KW, Tremaine WJ, Ilstrup DM: Coated oral 5-aminosalcylic acid therapy for mildly to moderately active ulcerative colitis. N Eng J Med 1987; 317 (26): 1625-1629.
  • Rutgeerts P, Sandborn WJ, Feagan BG, Reinisch W, et al. Infliximab for induction and maintenance therapy for ulcerative colitis. N Engl J Med. 2005; 353 (23): 2462-2476.
  • Lewis JD, Chuai S, Nessel L, Lichtenstein GR, Aberra FN, Ellenberg JH. Use of the noninvasive components of the Mayo score to assess clinical response in ulcerative colitis. Inflamm Bowel Dis. 2008; 14 (12): 1660-1666.
  • Turner D, Seow CH, Greenberg GR, Griffiths AM, Silverberg MS, Steinhart AH. A systematic prospective comparison of noninvasive disease activity indices in ulcerative colitis. Clin Gastroenterol Hepatol 2009; 7 (10): 1081-1088.