Secular growth trend of children and adolescents in Dadong District from 1981 to 2008

Objective To study the secular trend of height and weight among elementary and middle school students(aged 7-18) in Dadong District,Shenyang city from 1981 to 2008.Methods Data of height and weight in 1981,1991,2001 and 2008,which came from student physical examination in Dadong District,were compared with each other.Results Height and weight continued to increase from 1981 to 2008.Height increase trend showed slow down,increase amplitude of 1991-2001 and 2001-2008 showed smaller than that of 1981-1991,for 7-16 years old boys.The results showed that the age of growth spurt had an advanced tendency,for girls it began earlier 2 years in 2008 than that in 1981.The height cross interval between boys and girls showed reduced and narrowed gradually.Conclusion Height and weight of 7-18 years old students increases significantly in long-term trends and the timing of adolescence has an advanced tendency.