Table 1 Intra- and inter-observer 95% and 99.73% limits of agreement (LOA) for K1, K2, and TCT with the Pentacam HR, Orbscan IIz, and Casia SS-1000 in healthy (n = 30) and keratoconic eyes (n = 30), using one or the mean of three repeat measurements.
From: Improving precision for detecting change in the shape of the cornea in patients with keratoconus
Device | Parameter | Intra-observer agreement | Inter-observer agreement | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
1 Measurement | 1 Measurement | Mean of 3 measurements | |||||||||
SD | 95% LOA | 99.73% LOA | SD | 95% LOA | 99.73% LOA | SD | 95% LOA | 99.73% LOA | |||
Healthy eyes | Pentacam HR | Kmax | 0.15 | 0.35 | 0.51 | 0.21 | 0.41 | 0.63 | 0.11 | 0.20 | 0.31 |
K1 (D) | 0.08 | 0.15 | 0.24 | 0.09 | 0.19 | 0.29 | 0.04 | 0.08 | 0.12 | ||
K2 (D) | 0.09 | 0.17 | 0.27 | 0.13 | 0.23 | 0.37 | 0.07 | 0.11 | 0.18 | ||
TCT (μm) | 5.07 | 11.37 | 16.64 | 5.24 | 10.96 | 16.61 | 2.70 | 5.18 | 7.99 | ||
Orbscan IIz | K1 (D) | 0.21 | 0.99 | 1.58 | 0.59 | 0.99 | 1.61 | 0.30 | 0.61 | 0.82 | |
K2 (D) | 0.5 | 0.9 | 1.41 | 0.40 | 0.7 | 1.11 | 0.23 | 0.36 | 0.59 | ||
TCT (μm) | 9.48 | 17.95 | 27.81 | 9.37 | 18.1 | 27.85 | 4.91 | 10.21 | 15.32 | ||
Casia SS-1000 | K1 (D) | 0.17 | 0.34 | 0.52 | 0.22 | 0.43 | 0.66 | 0.09 | 0.19 | 0.28 | |
K2 (D) | 0.19 | 0.37 | 0.57 | 0.22 | 0.44 | 0.67 | 0.10 | 0.29 | 0.35 | ||
TCT (μm) | 1.33 | 2.14 | 3.53 | 1.78 | 2.8 | 4.65 | 1.18 | 1.85 | 3.07 | ||
Keratoconus | Pentacam HR | Kmax | 0.79 | 1.49 | 2.32 | 0.81 | 1.37 | 2.21 | 0.46 | 0.78 | 1.25 |
K1 (D) | 0.24 | 0.49 | 0.74 | 0.39 | 0.72 | 1.13 | 0.21 | 0.35 | 0.57 | ||
K2 (D) | 0.40 | 0.8 | 1.21 | 0.22 | 1.27 | 1.93 | 0.22 | 0.38 | 0.61 | ||
TCT (μm) | 5.9 | 12.19 | 18.33 | 6.98 | 13.71 | 20.97 | 3.39 | 6.4 | 9.93 | ||
Orbscan IIz | K1 (D) | 0.57 | 1.23 | 1.82 | 1.76 | 3.63 | 5.46 | 1.22 | 2.67 | 3.93 | |
K2 (D) | 0.65 | 1.18 | 1.86 | 2.28 | 4.85 | 7.22 | 1.54 | 3.20 | 4.80 | ||
TCT (μm) | 26.63 | 46.03 | 73.72 | 27.40 | 53.08 | 81.58 | 17.24 | 33.73 | 51.65 | ||
Casia SS-1000 | K1 (D) | 0.88 | 1.72 | 2.63 | 1.01 | 1.81 | 2.86 | 0.58 | 2.46 | 3.52 | |
K2 (D) | 1.55 | 2.89 | 4.50 | 1.69 | 3.48 | 5.23 | 0.76 | 1.39 | 2.19 | ||
TCT (μm) | 4.98 | 10.13 | 15.3 | 9.9 | 21.70 | 31.99 | 7.08 | 14.69 | 22.06 |