Table 3.

Correlations Between Food Frequency Questionnaire (FFQ) Estimates and the Mean of Three 24-Hour Dietary Recalls^a (n = 89), Berkeley, Calif, 2000

Nutrientb	Pearson Correlations
	Unadjusted	Energy Adjusted	Deattenuatedc
Energy, kcal	0.52	—	0.69
Protein, g	0.49	0.30	0.61
Carbohydrate, g	0.47	0.46	0.61
Fat, g	0.58	0.42	0.78
Percentage of energy from fat	0.41	—	0.56
Saturated fat, g	0.54	0.45	0.68
Cholesterol, mg	0.58	0.47	0.79
Dietary fiber, g	0.54	0.67	0.68
Sodium, mg	0.53	0.10	0.75
Calcium from food only, mg	0.43	0.42	0.58
Total calcium, including supplements, mg	0.43	—	0.43
Iron from food only, mg	0.48	0.31	0.67
Total iron, including supplements, mg	0.53	—	0.54
Vitamin A from food only, RE	0.27	0.33	0.36
Total vitamin A, including supplements, RE	0.52	—	0.53
Vitamin C from food only, mg	0.41	0.40	0.52
Total vitamin C, including supplements, mg	0.56	—	0.55

RE indicates retinol equivalents.

^aThe relationship between the FFQ and the 24-hour dietary recall nutrient values was estimated using Pearson correlation coefficients.

^bOnly nutrients for which at least 90% of the foods on the Food Processor database had a value for the nutrient. Log-transformed where needed to improve normality.

^cAdjusted for measurement error in dietary recalls.