Table.

Comparison of 84 Retinal Vessel Diameter Measurements Made From SLO Fundus Images of Elevated Optic Discs Using Manual and Semi-Automated Analysis Techniques

	Interobserver Comparison		Analysis Method Comparison
	Manual Analysis	Semi-Automated Analysis
Variability, mean, ±SD (mean, ±)	11 ± 8 μm (10% ± 8%)	3.2 ± 3.5 μm (2% ± 3%)
Pearson's correlation, r	0.90	0.98	0.85
Regression full model
Y-intercept (95% CI)	22.9 μm (−0.3 to 46.0)	7.3 μm (−4.8 to 19.4)	56.3 μm (30.2–82.4)
Slope (95% CI)	0.79 (0.62–0.96)	0.94 (0.86–1.03)	0.66 (0.46–0.86)
Vessel-dependent constant (95% CI)	−3.9 μm (−40.7 to 33.0)	−2.2 μm (−21.5 to 17.1)	−5.4 μm (−44.4 to 33.6)
Vessel-dependent slope (95% CI)	−0.06 (−0.40 to 0.28)	0.02 (−0.14 to 0.18)	0.0 (−0.36 to 0.37)
Regression final model
Y-intercept (95% CI)			42.3 μm (28.6–56.0)
Slope (95% CI)	0.91 (0.81–1.01)	0.95 (0.90–0.99)	0.75 (0.64–0.86)