Research

Mixed

Self-administered Food Frequency Questionnaires (FFQs) used in large cohorts provide valid estimates of macronutrient and food group intake, though they may underestimate micronutrient intake compared to 24-hour recalls.

Diet surveys are generally good at tracking big nutrient groups like fat and protein, but might miss precise amounts of certain vitamins and minerals.

GoodQualifiesHIGH confidence
For total energy and most nutrients, intakes assessed by the Nutrition Cohort FFQ were lower than those from the 24-hour dietary recalls... Median values for these micronutrients were influenced particularly by low correlation coefficients for zinc... and vitamin E...
Eugenia E. Calle et al. · Cancer · 2002

Why this rating

Based on validation study against 24-hour recalls.

Source

The American Cancer Society Cancer Prevention Study II Nutrition Cohort

Eugenia E. Calle et al. · Cancer · 2002

DOI 10.1002/cncr.10197

cohort · n=184194Cited 481×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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