Randomized, double-blinded, placebo-controlled trial evaluating simethicone pretreatment with bowel preparation during colonoscopy

Table 3 Inter-observer variability

Intraluminal bubbles grade	Kappa value	P-value
1	0.5687	< 0.001
2	0.2605	< 0.001
3	0.3481	< 0.001
4	0.5440	< 0.001
Combined	0.4024	< 0.001

Kappa statistic is a measure of agreement scaled 0 to be when amount of agreement is what would be due to chance and 1 when there is perfect agreement. Intermediate values suggest the following interpretations. Below 0.0 Poor, 0.01-0.20 Slight, 0.21-0.40 Fair, 0.41-0.60 Moderate, 0.61-0.80 Substantial, 0.81-1.00 almost perfect.