Development and validation of a Food Frequency Questionnaire for Brazilian adults, according to the NOVA classification.

Abstract

Introduction: The Nova classification that considers food processing was created in 2010. It has come to be used in epidemiological studies on the relationship between diet and chronic non-communicable diseases (NCDs). However, there is a common limitation in these studies which is the use of nonspecific food intake assessment instruments for Nova. This can lead to biases in the measurement of food intake and its effects. Objective: To develop and validate a food frequency questionnaire (QFA-Nova) that assesses usual food intake according to the Nova classification for Brazilian adults. Methods: The FFQ-Nova will be a self-administered quantitative frequency questionnaire for Brazilian adults. Its list of foods will be developed from the analysis of the most commonly consumed foods in the 2017-2018 Household Budget Survey, grouped according to Nova. It will undergo expert evaluation and review. Pre-testing will be conducted on a convenience sample of 20 people over 18 years old, residents of Brazil, of both genders. The necessary adjustments will be made, and the final version of the QFA-Nova is expected. For validation, we will use data from the NutriNet Brazil cohort, a prospective study that investigates the relationship between diet and NCD morbidity and mortality. We will invite 300 people from the five regions of Brazil through random selection. They will be informed about the details of the study and will read and agree to sign the Consent Form. Reproducibility will be assessed by comparing the data from two QFA-Nova. Validity will be carried out by comparing the data from the QFA-Nova with the data from three self-administered 24-hour recall.