Dietary Intake of Folic Acid and Vitamin B12 Among Teenage Girls - Validation of Food Frequency Questionnaire

Food frequency questionnaires (FFQs) are a common method for measuring dietary intake in large epidemiological studies, in particular in low literacy settings were diaries and food history would not be viable.

Standardized and validated approach of collecting all foods, beverages, and supplements consumed during the past 24 hours.