Cover Image
close this bookThe Functional Significance of Low Body Mass Index (IDECG, 1992, 203 p.)
close this folderBody mass index: its relationship with food consumption and socioeconomic variables in Brazil
View the document(introduction...)
View the documentIntroduction
View the documentMethods
View the documentResults
View the document1. BMI of adults and food consumption: some methodological issues
View the document2. BMI and socio-economic level
View the document3. The effect of age and sex on adult BMIs
View the document4. Adult BMI and morbidity
View the document5. Trends of BMI in Brazil
View the documentReferences
View the documentDiscussion

Methods

The ENDEF survey

This is a food consumption and family budget survey planned within the setting of the National Accounts to provide estimates for the expenditure on goods and services in the family sector. The survey also provides a substantial set of social indicators of the Brazilian population and the structure for several consumer price indices in the country. The nutritional objectives of the ENDEF survey were considered to be part of the social indicators which IBGE was developing at that time.

The ENDEF household survey used a non-self-weighted probabilistic sample of about 55000 households with about 230000 individuals and was designed to provide estimates appropriate to 22 geographical areas. The data were collected from August 1974 to August 1975 by almost 1000 enumerators divided into about 200 teams each headed by a supervisor. Each household was surveyed for 7 consecutive days with three or four daily visits (according to the number of meals prepared in the day) to weigh the food items that would be consumed in the next meal, their non-edible parts, as well as the food items purchased and the food items classified as 'waste', i.e. food not consumed and to be thrown out, given to domestic animals, given to other families or retained and consumed after the survey period in the household. For some food items, such as sugar, salt, seasonings, coffee etc., it was also necessary to weigh the family's stocks in order to estimate their consumption during the meal by taking the differences between the weights before and after the meal.

The visits were also used to record information, such as the attendance of residents and non-residents (guests, domestic employees, etc.) at the meals prepared, the household composition, individual data (sex, age, education level, weight, height, arm circumference, etc.) and the daily expenditure on food purchases, meals taken away from home, transport cigarettes, newspapers, etc.

After 3 or 4 days of survey, i.e. after gaining the family's confidence, the enumerator started collecting the data on family expenditure according to different recall periods (I month, 3 months and 1 year). On the final visits questions were asked about family income and savings. Using such methodology, it was possible to collect a set of very high quality data on food consumption as well as on household income and expenditure.

The information was recorded in a specially prepared questionnaire. Such data were then reorganized after entering and editing, in order to accommodate better the analysis. Some steps of the data reorganization will be mentioned in the following sections.

The PNSN survey

The second survey, Pesquisa Nacional de Sa Nutri (PNSN), was a national health and nutrition survey carried out in 1989. It was conducted by IBGE at the request of the Instituto Brasileiro de Alimenta e Nutri (INAN), the Brazilian Institute for Food and Nutrition that planned the survey, developed the questionnaire and supported most of the survey budget.

PNSN is a household survey with a non-self-weighted probabilistic sample of about 60000 individuals and 17 000 households, designed to provide estimates for nine geographical areas. It was a one-visit survey that collected data on household and individuals' characteristics. The individual data collection was divided into seven groups: general information; employment and income; education and attendance at school; children's information; women's information; morbidity; and anthropometric measures for everybody.