Adherence
Self-administered semi-quantitative food frequency questionnaires (FFQs) provide valid and reproducible estimates of long-term intake for frequently consumed foods (e.g., dairy, beverages), but significantly overestimate socially desirable foods (fruits/vegetables) and underestimate less desirable foods (animal products) due to social desirability bias.
Use food frequency questionnaires to compare relative dietary patterns between individuals, but do not rely on them for precise absolute intake estimates of specific foods. Be aware that users will likely over-report fruits and vegetables and under-report meats and fats due to social desirability bias.
This analysis documents the validity and reproducibility of the questionnaire for measuring specific foods and beverages... the observed differences suggested that responses to the questionnaire tended to over-represent socially desirable foods.
Why this rating
Large sample size (173 women), longitudinal design (12 months), and use of 28 days of dietary records as a gold standard comparator.
Source
Food-Based Validation of a Dietary Questionnaire: The Effects of Week-to-Week Variation in Food Consumption
Simonetta Salvini et al. · International Journal of Epidemiology · 1989
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →