Sistema de vigilância alimentar e nutricional: confiabilidade dos dados antropométricos de crianças menores de cinco anos da rede básica de saúde em Alagoas

Abstract

The Food and Nutritional Surveillance System of Brazil produces epidemiological information on health and nutritional situation of different life phases of the Brazilian Health System (SUS) users. This is done so as to subsidize the planning actions and the food and nutritional programs in the area of basic attention to health. In childhood, the monitoring of growth and development processes takes place mainly from anthropometric methods that are subjected to different sources of errors which can provoke significant distortions in the nutritional diagnosis. Therefore, the objective of this work was to investigate the reliability of the anthropometric data obtained in children under 5 years old of the SUS basic health system of Alagoas. An anthropometric profile of these children was made and the sampling was made in multiple stages, of three phases each, to obtain a sample of 40 Health Assistence Establishments (HAE) devoted to children medical care. Each child attended in the HAE had their measures verified at three different times, making possible interpersonal comparisons among them and among equipments. The harmony between the nutritional stage classification (from the NCHS, 1977), in relation to the indexes of weight for age (WA) and height for age (HA) was validated by the Cohen´s Kappa coefficient (K) and the interpretation by the Landis & Koch criteria. Variations were still analyzed in the measurements of body mass taking into account an acceptable variation of about 100 gr. in relation to the measure of the researcher when using a standard equipment. The anthropometric evaluation of the children was based on growth curves of the World Health Organization (WHO, 2006).The WHO Anthro program (2005) was used to calculate the z-scores. The cut-off points recommended by WHO (1995) were adopted for the nutritional diagnosis, which were associated to variables such as gender, age, localization of the Health Assistance Establishments (HAE) and the organizational model of the current basic attention. The data analysed in the Epi-Info were considered as statistically significant for p < 0.05. The results referred to the investigation reliability indicated substantial agreement (K=0.69) between the nutritional classifications of the WA index obtained by the professionals of the service. An improvement of the agreement (K=0.83) was observed when the researcher used service s equipment, suggesting errors in the evaluation technique of body mass by their professionals. In relation to HA index, the agreement was worrying (K=0.27) indicating serious problems of technical origin in the height checking up by the professionals as well as by the service s equipments, because it passed to moderate (K=0.56) when a comparison was made between the results produced by the researcher and those obtained by the researcher using the service s equipment. The results related to the anthropometric evaluation of the children under study indicated that malnutrition is present in two forms: height (8.4%) and weight (6.6%) deficit in relation to age, being the linear growth the one which was more compromised. The overweight tax (6.4%) already reaches malnutrition levels, showing a panorama of transitional nutrition. It was also observed that the children assisted by the Family Health Strategy (FHS) presented less malnutrition prevalence by weight deficit in relation to age (5.8%), being this difference significant. This situation may be attributed to the specific characteristics of FHS, among them the development of actions based on the situational diagnosis, with the family and the community as a focus, giving priority to the solution of the most frequent nutritional problems.