. Author manuscript; available in PMC: 2012 May 1.

Published in final edited form as: Ophthalmology. 2011 Mar 24;118(5):959–963. doi: 10.1016/j.ophtha.2011.01.054

Table 1.

Standardized differences of Matched Samples

	Control sample	Diabetes sample	Std Diff
Health comorbidities
Charlson comorbidity index	0.995	1.001	-0.327
Lipidemia	0.263	0.263	-0.009
Hypertension	0.562	0.562	0.024
Demographic characteristics
Age (in years)	76.429	76.379	0.786
Male	0.401	0.401	-0.032
Black race	0.110	0.110	-0.038
Other race	0.039	0.039	0.081

Observations	25,515	25,515

Std diff: Standardized differences =(100*(x_ti - x_nti))/(((s²_ti + s²_nti)/2)^0.5)_i