Web-based system for training and dissemination of a magnification chromoendoscopy classification

Table 1 Reproducibility for the classification in groups (I vs II vs III) and in subgroups (I vs IIE vs IIF vs III) according to number of times observers (A, B and C) classified the films of magnification chromoendoscopy

Number of classification (nth)	Inter-observer agreement (95% CI)
	Proportion of agreement	Weighted kappa
Classification in groups
1st observation	0.60 (0.36-0.81)	0.52 (0.26-0.75)
2nd observation	0.85 (0.62-0.97)	0.73 (0.53-0.87)
3rd observation	0.85 (0.62-0.97)	0.71 (0.51-0.86)
4th observation	0.95 (0.75-1.00)	0.97 (0.94-0.99)
5th observation	0.80 (0.56-0.94)	0.71 (0.50-0.86)
6th observation	0.90 (0.68-0.99)	0.94 (0.89-0.98)
Classification in subgroups
1st observation	0.45 (0.23-0.69)	0.49 (0.23-0.73)
2nd observation	0.55 (0.31-0.77)	0.69 (0.48-0.85)
3rd observation	0.45 (0.23-0.69)	0.66 (0.42-0.83)
4th observation	0.70 (0.46-0.88)	0.90 (0.81-0.96)
5th observation	0.60 (0.36-0.81)	0.66 (0.43-0.83)
6th observation	0.75 (0.51-0.91)	0.92 (0.84-0.96)

Table 2 Agreement with reference and validity measures for the classification in groups (I vs II vs III) and in subgroups (I vs IIE vs IIF vs III) according to number of times observers (A, B and C) classified the films of magnification chromoendoscopy (95% CI)

	Classification in groups I vs II vs III					Classification in Subgroups I vs IIE vs IIF vs III
	Pa	wK	Se	Sp	V	Pa	wK	Se	Sp	V
Observer A
1st observation	0.90 (0.68-0.99)	0.66 (0.32-0.85)	0.75 (0.56-0.94)	0.94 (0.83-1.00)	0.90 (0.77-1.00)	0.75 (0.51-0.91)	0.63 (0.29-0.84)	0.75 (0.56-0.94)	0.75 (0.56-0.94)	0.75 (0.56-0.94)
2nd observation	0.95 (0.75-1.00)	0.84 (0.64-0.93)	1.00	0.94 (0.83-1.00)	0.95 (0.85-1.00)	0.70 (0.46-0.88)	0.76 (0.50-0.90)	0.75 (0.56-0.94)	0.67 (0.46-0.88)	0.70 (0.50-0.90)
3rd observation	0.90 (0.68-0.99)	0.79 (0.54-0.91)	1.00	0.94 (0.83-1.00)	0.95 (0.85-1.00)	0.80 (0.56-0.94)	0.79 (0.55-0.91)	1.00	0.75 (0.56-0.94)	0.85 (0.69-1.00)
4th observation	1.00 (0.86-1.00)	1.00	1.00	1.00	1.00	0.90 (0.68-0.99)	0.97 (0.92-0.99)	1.00	0.83 (0.67-1.00)	0.90 (0.85-1.00)
5th observation	0.95 (0.75-1.00)	0.83 (0.63-0.93)	1.00	0.94 (0.83-1.00)	0.95 (0.85-1.00)	0.95 (0.75-1.00)	0.85 (0.66-0.94)	1.00	0.92 (0.79-1.00)	0.95 (0.85-1.00)
6th observation	1.00 (0.86-1.00)	1.00	1.00	1.00	1.00	1.00 (0.86-1.00)	1.00	1.00	1.00	1.00
Observer B
1st observation	0.90 (0.51-0.91)	0.80 (0.57-0.92)	0.75 (0.56-0.94)	1.00	0.95 (0.85-1.00)	0.65 (0.41-0.85)	0.71 (0.42-0.88)	0.50 (0.28-0.72)	0.83 (0.67-1.00)	0.70 (0.50-0.90)
2nd observation	0.90 (0.68-0.99)	0.77 (0.52-0.90)	0.75 (0.56-0.94)	1.00	0.95 (0.85-1.00)	0.80 (0.56-0.94)	0.78 (0.52-0.90)	0.75 (0.56-0.94)	0.92 (0.79-1.00)	0.85 (0.69-1.00)
3rd observation	0.90 (0.68-0.99)	0.77 (0.52-0.90)	0.75 (0.56-0.94)	1.00	0.95 (0.85-1.00)	0.70 (0.46-0.88)	0.69 (0.37-0.86)	0.63 (0.41-0.84)	0.75 (0.56-0.94)	0.70 (0.50-0.90)
4th observation	0.95 (0.75-1.00)	0.96 (0.90-0.98)	1.00	1.00	1.00	0.65 (0.41-0.85)	0.82 (0.60-0.92)	0.5 (0.28-0.72)	0.75 (0.56-0.94)	0.65 (0.44-0.86)
5th observation	0.90 (0.68-0.99)	0.77 (0.52-0.90)	0.75 (0.56-0.94)	1.00	0.95 (0.85-1.00)	0.65 (0.41-0.85)	0.73 (0.45-0.88)	0.63 (0.41-0.84)	0.92 (0.79-1.00)	0.80 (0.62-0.98)
6th observation	1.00 (0.86-1.00)	1.00	0.75 (0.56-0.94)	1.00	1.00	0.85 (0.62-0.97)	0.95 (0.87-0.98)	0.75 (0.56-0.94)	0.92 (0.79-1.00)	0.85 (0.69-1.00)
Observer C
1st observation	0.75 (0.51-0.91)	0.80 (0.57-0.92)	0.75 (0.56-0.94)	0.81 (0.64-0.99)	0.80 (0.62-0.98)	0.60 (0.36-0.81)	0.82 (0.60-0.92)	0.75 (0.56-0.94)	0.83 (0.67-1.00)	0.80 (0.62-0.98)
2nd observation	0.95 (0.75-1.00)	0.96 (0.89-1.00)	1.00	1.00	1.00	0.60 (0.36-0.81)	0.85 (0.67-0.94)	0.50 (0.28-0.72)	0.75 (0.56-0.94)	0.65 (0.44-0.86)
3rd observation	0.85 (0.62-0.97)	0.72 (0.42-0.88)	1.00	0.84 (0.67-1.00)	0.85 (0.69-1.00)	0.50 (0.27-0.73)	0.65 (0.31-0.84)	0.38 (0.16-0.59)	0.75 (0.56-0.94)	0.60 (0.38-0.82)
4th observation	0.95 (0.75-1.00)	0.96 (0.89-0.98)	1.00	1.00	1.00	0.70 (0.46-0.88)	0.89 (0.74-0.95)	0.5 (0.28-0.72)	0.92 (0.79-1.00)	0.75 (0.56-0.94)
5th observation	0.85 (0.62-0.97)	0.74 (0.47-0.89)	0.75 (0.56-0.94)	0.94 (0.83-1.00)	0.90 (0.77-1.00)	0.65 (0.41-0.85)	0.73 (0.45-0.88)	0.63 (0.41-0.84)	0.83 (0.67-1.00)	0.75 (0.56-0.94)
6th observation	0.90 (0.68-0.99)	0.92 (0.81-0.97)	1.00	0.94 (0.83-1.00)	0.95 (0.85-1.00)	0.80 (0.56-0.94)	0.93 (0.84-0.97)	0.88 (0.73-1.00)	0.92 (0.79-1.00)	0.90 (0.77-1.00)

Pa: Proportion of agreement; wK: Weighted kappa, Se: Sensitivity; V: Validity.