Estimating the prevalence of height for age deficits based on the prevalence of low weight for age among Brazilian children

Abstract

INTRODUCTION: Anthropometry is frequently used for evaluating nutritional status of individuals and populations. In recent years, community surveys have been conducted by health professionals in various regions of Brazil with the objective of complementing the data obtained through nutritional surveillance programs. One important difficulty in conducting these assessments has been measuring height during visits to the homes of survey participants. METHODS: Thirty-eight anthropometric surveys of Brazilian children aged up to 5 years using the National Center for Health Statistics (NCHS) reference were identified. The percentage of children with a Z-score below standard deviations was used to define deficits of weight for age and height for age. RESULTS: Correlation between prevalences of height for age and weight for age deficits were examined. Due to the low prevalence of deficits in weight for height in all surveys, there was a strong correlation between weight for age and height for age at the population level. Approximately 90% of the height for age (H/A) variation was accounted for by that of weight for age (W/A). CONCLUSIONS: Using the equation, (Prevalence H/A) = 0.74 + 2.34 (Prevalence W/A) - 0.03 (Prevalence W/A)² it is possible to estimate the prevalence of height deficits on the basis of prevalence of weight deficits. These results suggest that anthropometric surveys as conducted in Brazil, in the context of health services, can be simplified by measuring weight only, instead of both weight and height.