Design and analysis of food frequency questionnaires - review and novel method

Abstract

A novel method is proposed for the design and analysis of a food frequency questionnaire facilitated by a computer program. The method relies on a weighed inventory undertaken by a sample of the population that is combined into a database along with the nutrient analyses of the foods consumed. The program provides an interface that enables the researcher to see the total amount of each food that was consumed, decide on what questions to ask and allocate the relevant foods to these questions. The approach means that all foods consumed can appear in the questionnaire. The nutrient analysis for each question is a weighted mean depending on the inventory. The portion weight employed for each question is derived from the weights of foods consumed in the inventory and any misperceptions in the frequency of consumption of all the subjects are corrected by calculating a factor to multiply by the frequency from the questionnaire. A viability study established the practicability of the method.