Performance of the Montreal classification for inflammatory bowel diseases

Table 1 Montreal classification of Crohn’s disease, ulcerative colitis, non-classified chronic colitis and indeterminate colitis

Diagnosis (20 case-vignettes)
Crohn’s Disease (CD)
Ulcerative Colitis(UC)
Non-classified chronic colitis (IBD-U)
Indeterminate colitis (IBD-I)
Age of onset (A) (20 case-vignettes)
A1: 16 yr or younger
A2: 17-40 yr
A3: over 40 yr
CD (10 case-vignettes)	UC, IBD-U, IBD-I (10 case-vignettes)
Localization (L)	Disease extent (E)
L1: Terminal ileum	E1: Proctitis
L2: Colon	E2: Left-sided UC; proximal extent of inflammation is distal to the rectosigmoid
L3: Ileocolon
L4: Upper gastrointestinal	E3: Extensive UC; involvement extends proximal to the splenic flexure.
P: Perianal disease
Behavior (B)	Disease severity (S)
B1: Nonstricturing, nonpenetrating B2: Stricturing B3: Penetrating	S0: Remission, no symptoms S1: Mild, ≤ 4 ×/d stools, no systemic signs of toxicity, normal ESR S2: Moderate, > 4 ×/d stools, minimal systemic signs of toxicity S3: Severe, ≥ 6 ×/d stools, pulse > 90 beats/min, temperature > 37.5, Hemoglobin < 6.5 mmol/L, ESR > 30 mm

EIM: Extra-intestinal manifestations; ESR: Erythrocyte sedimentation rate.

Table 2 Characteristics of 30 observers n (%)

	< 10 yr of experience with IBD patients	10-20 yr of experience with IBD patients	> 20 yr of experience with IBD patients	Non-university center	University medical center	Total
Gastroenterologist	7 (23%)	5 (17%)	4 (13%)	5 (17%)	11 (37%)	16 (54%)
Gastroenterologist in training	10 (33%)			3 (10%)	7 (23%)	10 (33%)
IBD-nurse	3 (10%)	1 (3%)		1 (3%)	3 (10%)	4 (13%)
Total	20 (67%)	6 (20%)	4 (13%)			100%

IBD: Inflammatory bowel disease.

Table 3 Percentages of correct answers according to the “expert evaluation” for overall and divided for different professions

	Overall correct answers	Gastroenterologist	Gastroenterologist in training	IBD-nurse
Age of onset	94.0%	94.2%	96.8%	86.0%
Diagnosis	96.9%	96.0%	96.0%	98.8%
CD disease Localization	94.0%	90.6%	93.8%	97.5%
CD upper gastrointestinal	91.3%	95.6%	94.0%	84.2%
CD perianal disease	98.0%	99.4%	98.0%	96.7%
CD Disease behavior	92.4%	92.4%	94.8%	90.0%
CD severity (mild, moderate, severe)	73.9%	68.7%	72.9%	80.0%
UC disease extent	84.0%	89.3%	85.2%	77.5%
UC disease severity colitis	50.7%	53.9%	50.7%	47.5%
EIM	82.1%	82.1%	85.8%	78.5%

EIM: Extra-intestinal manifestations; CD: Crohn’s disease; UC: Ulcerative colitis.

Table 4 Percentages of correct answers compared to the “expert evaluation” overall and divided for different years of experience with inflammatory bowel disease patients

	Overall correct answers	< 10 yr of experience	10-20 yr of experience	> 20 yr of experience
Age of onset	92.3%	95.2%	93.0%	88.6%
Diagnosis	96.2%	97.0%	93.3%	98.3%
CD disease localization	90.6%	94.2%	90.0%	87.5%
CD upper gastrointestinal	94.8%	91.8%	100.0%	92.5%
CD perianal disease	98.9%	98.5%	98.3%	100.0%
CD disease behavior	93.0%	92.3%	96.7%	90.0%
CD severity (mild, moderate, severe)	69.9%	73.1%	70.0%	66.7%
UC disease extent	86.6%	86.2%	85.3%	88.3%
UC disease severity colitis	48.0%	56.2%	37.7%	50.0%
EIM	83.4%	82.7%	81.6%	86.0%

EIM: Extra-intestinal manifestations; CD: Crohn’s disease; UC: Ulcerative colitis.

Table 5 Inter-rater agreement kappa for all items of all categories of Montreal classification

Item Montreal classification	Overall kappa
Age of onset	0.67 (n = 28)
Diagnosis	0.96 (n = 28)
CD disease localization	0.82 (n = 28)
CD upper gastrointestinal	0.62 (n = 28)
CD perianal disease	0.91 (n = 28)
CD disease behavior	0.79 (n = 26)
CD severity (mild, moderate, severe)	0.44 (n = 24)
UC disease extent	0.65 (n = 21)
UC disease severity colitis	0.23 (n = 20)
EIM	0.68 (n = 28)

Observers were only included if they scored at least one item in all case-vignettes. EIM: Extra-intestinal manifestations; CD: Crohn’s disease; UC: Ulcerative colitis.