Discovering a secular trend through a cross-sectional study

Abstract EN

It has been observed that the younger generation in Saudi Arabia is taller than the middle-aged, not to mention the elderly, with a height difference that exceeds the aging effect.

This observation leads naturally to speculation regarding the existence of a secular trend.

Such a speculation is realistic, since Saudi Arabia is an oil producing country and probably has the largest per capita oil output in the world.

The oil revenues have created a strong economy and good living standards, which probably has contributed to the apparent secular trend.

Discovering a secular trend in a certain nation takes usually a decade or more .

In today’s fast moving world, it may be of interest to seek ways to discover the change in body dimensions in a period shorter than a decade.

This study proposes an approach using the cross-sectional method to show the existence of a secular trend, which should take months rather than years.

The study uses the Saudi population as an example.

Ten body dimensions of 693 Saudi males have been taken across an age group ranging from 20 to 69 years.

A methodology is presented to show how this cross-sectional study may be used to find out the secular trend.

The results reveal the existence of a secular trend in stature at the rate of 1 cm per decade and this change is basically contributed by the legs.