Table 1.

Kappa values for inter- and intra-observer variation for the Schatzker classification

	Inter-observer						Intra-observer
	A	B	C	D	E	F
A		0.42	0.50	0.29	0.39	0.45	0.53
B			0.53	0.40	0.32	0.47	0.65
C				0.46	0.38	0.55	0.70
D					0.32	0.33	0.36
E						0.38	0.51
F							0.66
Mean κ value for each observer	0.41	0.43	0.48	0.36	0.36	0.44
Mean κ value for all observers	0.41						0.57

A and B were consultants, C and D were SpRs, E and F were research fellows.