Continuity of leanness/obesity from childhood to adolescence.

Continuity and changes in leanness/obesity were studied following growth of the same individuals born in 1966 to 1968. Data on height and weight at ages 11, 14 and 18 were available for 770 boys and 1070 girls, and Rohrer's and Quetelet's indices were calculated from the data. In both indices, there were significant correlations between the values of the same individuals at age 11 and at age 14, and also at age 11 and at age 18. The subjects were divided at each age into 10 ranks of equal size so that those in Rank 1 (lean) and Rank 10 (obese) had the lowest and the highest index, respectively. The rate of those who were in Rank 1 or Rank 10 at age 11 but in medium ranks (Ranks 4-7) at age 18 was about 10 (lean) or 22% (obese) among boys, and 17 (lean) or 15% (obese) among girls when based on Rohrer's index. The analysis with Quetelet's index gave similar results. Children in the medium ranks also shifted into other ranks as they grew. Weight was more powerful than height as the determinant of the shifts from lean/obese to medium and also from medium to lean/obese ranks.