TABLE 2.

Fraction of WHI NPAAS Feeding Study (n = 153) intake variation explained (R²) by linear regression of log-intake on intake measures and covariates¹

Nutritional variable	Log(serum) concentration and covariates	Log-serum concentration, log(FFQ) intake, and covariates2
CVD covariates
α-Carotene	0.535	0.528
β-Carotene	0.415	0.462
Lutein + zeaxanthin	0.443	0.512
α-Tocopherol	0.547	0.572
Cancer covariates
α-Carotene	0.528	0.523
β-Carotene	0.346	0.411
Lutein + zeaxanthin	0.447	0.499
α-Tocopherol	0.530	0.552
Diabetes covariates
α-Carotene	0.520	0.515
β-Carotene	0.371	0.451
Lutein + zeaxanthin	0.432	0.490
α-Tocopherol	0.528	0.553

¹Covariates considered for inclusion in regression models for CVD, cancer, and diabetes analyses are listed in Supplemental Table 1. Covariates are included through forward selection with a P value threshold of 0.1 and are retained using the same P = 0.1 criterion. CVD, cardiovascular disease; NPAAS, Nutrition and Physical Activity Assessment Study; R², % of variation in response variable explained by regression variable(s); WHI, Women's Health Initiative.

² R ² values may be less than that for the model without FFQ due to missing FFQ data.