Non-linear law-like relationship between weight & height of infants & pre-school children.

A non-linear equation of the type log w - 0.008 h = a - be-kl for weight (w) and height (h) of 1177 infants and pre-school children from the Rural Health Centre area in Ballabhgarh was fitted by modified Guass-Newton Method using BMDP 03R program. On applying the non-linear model to the data of the present study it was found that the curve was a good fit in both sexes and also in all nutritional groups. The value of 'a' (the nutritional index) was almost the same in boys and girls but it was higher in case of children with normal nutrition (0.37) and lower in children with malnutrition (0.34 in Grade I, 0.32 in Grade II and 0.28 in Grades III & IV). The exponential term 'k' (index of maturation) was higher in boys compared to that of girls and higher in those with normal nutrition than with malnutrition. It was found that the rate of decay of the exponential term was slower in those with malnutrition compared to those with normal nutrition. While no difference was observed in the asymptotic value i.e., the rate at which infants reach the shape of older children, between boys and girls with normal nutrition (19 and 20 months respectively), it was delayed by 5 to 8 months in girls compared to boys with malnutrition. In the total sample, the Ehrenberg's index attained the asymptotic value at 20 months in boys and at 35 months in girls and at 27 months in the combined sample.

Age at which chest circumference overtakes head circumference in children.

Maximum likelihood method with probit transformation was applied to estimate median age at which chest circumference (CC) overtook head circumference (HC) in 1206 children from rural areas of Ballabhgarh in Haryana and in 1505 children from a slum population in Delhi. The results showed that, in case of rural area, this phenomenon occurred at an average age of 31.36 months and in children from urban slums, at an average age of 28 months. In both the areas, this phenomenon occurred at an average age of 20 to 21 months in normally nourished children. In children with grade I malnutrition, this was delayed by about 10 months as compared to those with normal nutrition and in children with grade II or worse malnutrition, this was further delayed by another 9 to 13 months on an average as compared to those with grade I malnutrition. These differences were found to be statistically significant (p < 0.001). These results indicate that the longer the delay in CC overtaking HC, the chance is higher for the children to be severely malnourished. Considering the relative ease of measuring head and chest circumferences, this parameter (age of CC crossing HC) could be useful in assessing the long term trend in the improvement of childhood nutrition in developing countries.