Food consumption scale validation in VAMOS Program: a proposal to assess eating behavior changes in Brazil

This study aimed to validate the frequency consumption scale (FCS) and establish cut-off points to assess changes in the eating behavior of participants in the VAMOS Program. The study was based on a community intervention conducted in 2019 in 70 Brazilian cities, with 458 adults from Primary Care. The questionnaire consisted of 12 questions about food frequency consumption. The questions were inserted into the analytical workflow, divided into the descriptive analysis, exploratory and confirmatory factor analysis (EFA), item response theory (IRT) modeling, and construction and validity of an applied questionnaire score. EFA indicated a two-factor structure, with three "healthy" (raw vegetables, fruits, and cooked vegetables) and three "unhealthy" (sugary drinks, sweets, and the replacement of meals with snacks) eating items. Items responses' probabilities indicate a daily consumption of two healthy and once or nonweekly consumption of unhealthy items. Finally, the four categories proposed for FCS can respond over time. Therefore, the FCS proposal can be used effectively for program nutrition evaluation. Furthermore, it is possible to attribute behavior change in Brazilian primary care users with six items.