Comparison of weighed food record procedures for the reference methods in two validation studies of food frequency questionnaires.

Background: Although open-ended dietary assessment methods, such as weighed food records (WFRs), are generally considered to be comparable, differences between procedures may influence outcome when WFRs are conducted independently. In this paper, we assess the procedures of WFRs in two studies to describe their dietary assessment procedures and compare the subsequent outcomes.

Methods: WFRs of 12 days (3 days for four seasons) were conducted as reference methods for intake data, in accordance with the study protocol, among a subsample of participants of two large cohort studies.

Validity of a food frequency questionnaire in a population with high alcohol consumption in Japan.

Background And Objectives: Alcohol consumption has a relatively large impact on energy intake in drinkers, and several studies reported different dietary habits from non-drinkers. However, few studies have investigated the influence of alcohol consumption on the validity of the Food Frequency Questionnaire (FFQ). To investigate its influence, we conducted a validity test in a population with high alcohol consumption.