Table 3.

Differences in measurements and their 95% confidence interval (CI), 95% limit of agreement, 95% tolerance for change, and the intraclass correlation coefficients (ICC) and their 95% CI of (i) second reading − first reading of area cup-disc ratio (ACDR) measured with HRT and Discam by observer A, (ii) observer A − observer B estimation of ACDR measured by HRT and Discam, and (iii) HRT − Discam when measuring ACDR by observer A and B

	Differences between measurements (mean (SD))	95% confidence interval (CI)	95% limit of agreement (mean (2SD))	95% tolerance for change	ICC (95% CI)
HRT ACDR 2nd reading − 1st reading (observer A)	−0.003 (0.047)	−0.015 to 0.009	−0.1 to 0.009	11.04	0.97 (0.96 to 0.98)
Discam ACDR 2nd reading − 1st reading (observer A)	−0.029 (0.041)	−0.039 to –0.019	−0.11 to 0.05	15.09	0.92 (0.76 to 0.97)
HRT ACDR (observer A − observer B)	−0.023 (0.043)	−0.033 to −0.013	−0.11 to 0.063	10.46	0.97 (0.94 to 0.99)
Discam ACDR (observer A − observer B)	−0.029 (0.0770)	−0.047 to −0.011	−0.18 to 0.125	24.54	0.79 (0.66 to 0.87)
HRT ACDR − Discam ACDR observer A	−0.082 (0.122)	−0.11 to −0.052	−0.33 to 0.16	24.78	0.67 (0.33 to 0.82)
HRT ACDR − Discam ACDR observer B	−0.075 (0.16)	−0.037 to 0.11	−0.25 to 0.40	46.67	0.53 (0.30 to 0.70)