Analysis of the adolescent growth spurt using smoothing spline functions

Abstract

Height growth velocity curves between 4.5 and 17.75 years were estimated, using smoothing spline functions, for 112 boys and 110 girls from the Zurich Longitudinal Study (1955--1976). Parameters characterizing the growth process, such as peak height velocity and age at peak height velocity, were calculated directly from the estimated curves. The variability of parameters describing the adolescent growth spurt is large, both between and within sexes. Peak height, defined as increase of height velocity during the growth spurt, and age at peak height velocity both characterize the sex difference in growth in a highly significant manner. Peak height of at least 4 cm/year is found in 70% of the boys, but in only 11% of the girls. The age at peak height velocity averages 12.2 years in girls and 13.9 years in boys and has a wide range of 5.7 years and 3.8 years respectively. The sex difference in adult height of 12.6 cm is composed of the following 4 factors: +1.6 cm caused by more prepubertal growth in boys, +6.4 cm by the boys' delay in spurt, +6.0 cm by the more extensive spurt in boys and -1.4 cm by more post-spurt growth in girls. Correlations between parameters indicate that the adult height depends neither on the duration of growth, nor on the duration and height of the peak. Minimal pre-spurt height velocity and peak height velocity, but not peak height, are age- and height-dependent. Partial correlations given adult height reveal two compensating mechanisms between growth in the prepubertal and in the pubertal period. Small prepubertal height and low height velocity with respect to adult height are followed by a late adolescent spurt and vice versa. Small height at the onset of the spurt with respect to adult height is followed by a longer lasting, but not higher spurt and vice versa.

Secular Change and Socioeconomic Difference in Height in Japan.

“…Here it is 9 for boys and 7 for girls, which is about 3.5 years younger than the youngest PHV age calculated in the previous section. According to the data of Kato et al (1992), who studied PHV age of children who were born in the 1960s and living in Tokyo, the adolescent spurt may have started in a few children at RA, but the effects would be small because age at onset of spurt is about 2.5 years younger than PHV age (Largo et al, 1978).…”

“…(4) Age at peak height velocity Figure 5 shows the secular change in age at peak height velocity (PHV age), calculated according to Hoshi and Kouchi (1981) using the School Health series in the population-follow-up manner. PHV age is an indicator of the timing of the adolescent spurt (Largo, 1978). Increase in height and an earlier adolescent spurt are often discussed together because height increase in children is partly due to accelerated growth.…”

Relationship between body composition and BMI in preschool children

“…Matsuura and Kim [17](1991) applied the least square approximation polynomials to height and weight growth and investigated their growth patterns. Largo et al [18] applied spline smoothing in a study of height growth patterns.…”

Verification Regarding Secular Trend of Height Growth and The Maximum Peak Velocity during Adolescence

“…Matsuura and Kim (1991) applied least square approximation polynomials to growth of body height and weight and examined their growth patterns. Much earlier, Largo et al (1978) examined growth patterns of height by applying a Spline smoothing method. In both studies, least square approximation polynomials were applied to draw helpful knowledge.…”