Effect of age, sex, race/ethnicity, and obesity on the relation of glycemic measures to Si and AIR. In linear regression models with Si as the dependent variable, age, sex, race/ethnicity, and center were included as covariates. Effect of age, sex, race/ethnicity, and obesity on the relation of glycemic measures to Si and AIR. In linear regression models with Si as the dependent variable, age, sex, race/ethnicity, and center were included as covariates. In models with AIR as the dependent variable, age, sex, race/ethnicity, research center, and Si were included as covariates. Continuous variables were log transformed to meet the specifications of the test. Estimates are expressed per 1 SD unit change. Carlos Lorenzo et al. Dia Care 2010;33:2104-2109 ©2010 by American Diabetes Association