Desenvolvimento, validação e reprodutibilidade de um questionário de frequência alimentar para gestantes

Abstract

The food frequency questionnaire is widely applied in epidemiological studies that assess the relationship between diet and disease, since it is considered the most practical method of assessing the usual dietary intake in a retrospective period of time. This dissertation is structured in three sections, with a literature review chapter fragmented into six topics, with the objective of discussing, through theoretical framework, existing food surveys, variations and measurement errors, methods for the preparation, validation and reproducibility of a questionnaire. food frequency and food frequency questionnaires existing in Brazil for the pregnant population. For the second section, an original article was prepared, entitled “Development of a food frequency questionnaire for pregnant women in northeastern Brazil”, it is a cross- sectional study, carried out with a sample of pregnant women from a larger study carried out in the public health network . The food frequency questionnaire was developed according to the percentage of relative food distribution for the nutrients of interest (energy, proteins, carbohydrates, lipids, calcium, iron, zinc, vitamins A, E, C, B12 and folate). The instrument has portion size, number of times food is consumed and frequency of consumption (daily, weekly and monthly). The final list of the questionnaire resulted in 112 food items grouped according to the Food Guide for the Brazilian Population. The third section consists of the original article, entitled “Validation and reproducibility of a food frequency questionnaire to assess the food consumption of pregnant women in northeastern Brazil”. Study of construction and validation of a food frequency questionnaire, carried out with pregnant women attended in the public health network of the city of Maceió, in 2019. The questionnaire was evaluated for accuracy and precision, in which for validation adequate correlation coefficients were identified for energy, carbohydrate, vitamin B2, B5, E, B12, phosphorus, magnesium, selenium, cholesterol, saturated fat, polyunsaturated and monounsaturated fat, fibers. High intraclass correlation coefficients were identified for magnesium, iron, lipid and energy and lower for manganese, vitamin B12 and vitamin D. The developed food frequency questionnaire is a useful tool to be used in the context of research, determining the usual food consumption of women pregnant.