A Critical Assessment of Friedenwald’s Technique for Estimating the Coefficient of Rigidity of the Cornea

Table 3

Intersessional differences in Ko estimations. 1 = Ko values estimated by operator 1. 2 = Ko estimated by operator 2. Figures in parentheses are the number of individual cases in each group.

	Mean	Median	Mode	±sd	95% CI	Range
1, 1^st session (27)	0.020	0.020	0.025	0.011	0.016–0.024	0.008–0.051
1, 2^nd session (27)	0.016	0.015	0.011	0.008	0.013–0.019	0.008–0.047
2, 1^st session (16)	0.016	0.013	0.015	0.012	0.010–0.021	0.006–0.054
2, 2^nd session (16)	0.018	0.013	0.025	0.012	0.012–0.024	0.007–0.047