Table 2.

The Relationship of Covariates to Absolute Differences in Retinal Vessel Measurements from Two Photographs Taken Consecutively.

	Absolute Difference in Vessel Measurements
Covariate	β estimate (SE)*	P value
Central Retinal Arteriolar Equivalent
Age (per 5 years)	0.20 (0.14)	0.15
Sex (men vs. women)	0.69 (0.70)	0.33
Image focus
Both photos fair or worse vs. both photos good or excellent	5.03 (2.51)	0.04
Photos have different quality vs. both photos good or excellent	−0.07 (0.70)	0.92
Central Retinal Venular Equivalent
Age (per 5 years)	−0.02 (0.18)	0.89
Sex (men vs. women)	0.09 (1.03)	0.93
Image focus
Both photos fair or worse vs. both photos good or excellent	−0.74 (1.23)	0.54
Photos have different quality vs. both photos good or excellent	0.69 (0.65)	0.28

^*SE, standard error.