Table 2.

Comparison of Agreement with Diagnostic Modalities Compared with Slit Lamp Examination

Testing Modality	Mean Difference, % (SE)	Limits of Agreement	% Outside LOA	P value*
Examiners	−1.77 (−6.35 to 2.81)	−22.44 to 18.89	4.55	0.31
AS-OCT	−9.60 (−18.66 to −0.54)	−50.47 to 31.27	13.64	0.008
Pentacam	10.35 (−3.63 to 24.32)	−45.85 to 66.54	16.67	0.12
USP	21.83 (5.44 to 30.82)	−38.93 to 82.49	5.56	0.07

Paired comparisons of % corneal thinning as measured by two masked graders with slit lamp examination, and mean grade by slit lamp compared with AS-OCT, Pentacam and USP. Abbreviations: SE, Standard Error of the measurement; LOA, Limits of Agreement; AS-OCT, Anterior Segment Optical Coherence Tomography; USP, Ultrasonic Pachymetry

^*Pitman’s test of difference in variance