Linked cross-sectional study for determining norms and growth rates- a pilot survey on Indian school-going boys

Abstract

The paper deals with the statistical analysis of measurements obtained on school-going boys of various ages for estimating norms and growth rates, in what is termed as an LCS (Linked Cross-Sectional) study. This is a cross between a longitudinal study where some boys are chosen at a fixed young age and are measured periodically over a certain number of years covering the range of study, and a cross-sectional study where boys of different ages are chosen and each boy is measured only at one age and at one point of time. In an LCS study, boys of different ages are chosen and each boy is measured periodically over a comparatively smaller number of years. Thus, if one is interested in studying growth of boys between the ages of 5 and 16, a certain number of boys at each age (between 5 and 16) may be chosen and measured on three consecutive birth days. The study is thus restricted to a period of about 2 years, whereas a longitudinal study the period will be about 11 years. The advantages of such a short range study compared to a purely longitudinal study extended over a larger number of years are explained.