Table 2. Inter- and intra-observer reliability.

	Inter-observer	Intra-observer
C0-1 at hyperflexion	0.683 (0.661-0.718)	0.891 (0.862-0.917)
C0-1 at neutral position	0.739 (0.695-0.757)	0.912 (0.889-0.935)
C0-1 at hyperextension	0.710 (0.664-0.711)	0.909 (0.869-0.920)
Ratio (E/F of C0-1)	0.968 (0.922-0.997)	0.981 (0.976-0.989)

The intraclass correlation coefficients (ICC) for the intra-observer reliabilities of the ratio were excellent, however, the inter-observer reliabilities of distances for each group were unsatisfactory.