A Dietary Supplement Frequency Questionnaire Correctly Ranks Nutrient Intakes in US Older Adults When Compared to a Comprehensive Dietary Supplement Inventory.

A self-administered short SFQ can be used in large surveys to identify participants who use 16 categories of dietary supplements at least once a week and can correctly rank participant intakes of nutrients. However, the SFQ does not accurately estimate absolute levels of nutrient intakes from supplements.