Characteristics of the overall population and by self-identified race/ethnicity.

aMean sample size for 15 datasets; total counts may not always add up as numbers were not the same for all 15 data sets (the number deleted was based on imputed values for each data set); the percentages may not add up to 100% due to rounding;bmeans and percentages are weighted;cdata not available for 533 participants;dbetween BACH I and III,ebetween BACH II and III; CI = confidence interval; p25 = lower quartile; p75 = upper quartile.Characteristics of the overall population and by self-identified race/ethnicity.