Comparison of Gomez and Waterlow classifications in a follow-up study among pre-school children

Two classifications, widely used for assessing malnutrition, those of Gomez and Waterlow, were examined for concordance in a follow-up study. Unlike in cross-sectional studies, the classifications should reflect the changes in the nutritional status of individuals over a period of time. A method of cross-classification is illustrated for assessing these changes. Data were collected on 95 children from a village and on 74 children from an urban slum. Children were measured twice for weight and height, at an interval of 17 months in the village and 12 months in the slum. The usual way of comparing estimates of malnutrition in the initial and final rounds of a follow-up study would not reveal the shifts of individuals from one grade to another grade of malnutrition. The method illustrated in this paper, on the contrary, is able to identify individuals who improve, deteriorate or show no change in their nutritional status. It was found in this follow-up study that identical conclusions were reached by both classifications in only about 17 per cent of the children, whereas about 40 per cent showed only partial concordance (ie, between Gomez and either wasting only or stunting only).