Table 4.

Intraclass correlation coefficient (ICC) for curvature readings in Pentacam and Orbscan by keratoconus grades.

	Grade 1	Grade 2	Grade 3
Pentacam
1 mm ring	0.989	0.985	0.902
2 mm ring	0.990	0.978	0.890
3 mm ring	0.993	0.983	0.863
4 mm ring	0.993	0.958	0.851
5 mm ring	0.979	0.969	0.866
Orbscan
1 mm ring	0.972	0.900	0.821
2 mm ring	0.969	0.750	0.298
3 mm ring	0.970	0.828	0.888
4 mm ring	0.973	0.907	0.941
5 mm ring	0.958	0.887	0.929