The purpose of this study was to determine the extent to which sex, ag
e, height, and weight predict selected physiologic outcomes, namely, f
orced expiratory volume in one second (FEV1), hemoglobin concentration
, food intake, serum glucose concentration, total serum cholesterol co
ncentration, and cancer-related weight change. Secondary analysis was
performed on four datasets with sample sizes ranging from 60 to 8,489.
FEV1 (R-2 = .56), hemoglobin (R-2 = .40), food intake (R-2 = .25), gl
ucose (R-2 = .24), cholesterol (R-2 = .21 and .15), and cancer-related
weight change (R-2 = .16 and .06) were predictable to varying extents
. Moreover, the use of sex, age, height and weight as covariates and i
n sample size determination was shown to be relevant when testing the
effects of interventions or other variables on these physiologic outco
mes.