The present investigation characterizes common growth tracks in pre-pubertal children. Growth tracks denominate areas of probability within which subsequent measurements of the body height (or body height SDS) of a healthy individual will predominantly be found. Growth tracks are defined over several years and they are insensitive to the timing of measurements. The concept of growth tracks was developed to improve separating aberrant patterns from normal growth. Longitudinal data on height were obtained from six large national growth studies, performed at Berkeley, USA, Jena, Germany, Lublin, Poland, Paris, France, Prague, Czech Republic and Zurich, Switzerland with a total of 515 healthy boys and 532 healthy girls. Four hundred and two series of annual height measurements were available in pre-pubertal boys (aged 3-11 years), 416 series in pre-pubertal girls (aged 3-10). Body height was converted into height SDS. Thereafter, average personal height SDS was determined, and subtracted from height SDS, resulting in individual series of residual height SDS. These were sorted by cluster analysis and distributed into groups (clusters) according to similarity or dissimilarity (squared difference). We identified similar clusters, and named them 'growth tracks'. We found five pre-pubertal male growth tracks, each containing between 4 and 37% of the boys. Twenty boys could not be assigned to either one of the five tracks. Very similar results were obtained in girls, with five pre-pubertal growth tracks also, each containing between 3 and 50%. Twenty-three individuals grew irregularly and could not be assigned. Growth tracks are narrow, with an average width between 12.1 and 14.8% of the SD of body height. Most children exhibited almost horizontal height SDS patterns. Others showed linearly declining, rising, or intersection -shaped patterns. None of the patterns were predominantly found in particularly short or tall children. Preliminary data support the practical advantages of the concept of growth tracks.

No abstract

The effect of determinants of growth in body length from birth to 6 years of age were studied in a longitudinal sample of 59 male and 70 female infants from Lublin, Poland. Structural equation modeling (SEM) was used to study the effects of gender of the child, occupation of the parents, the educational level of the parents, per capita income, the stature of the parents, and the weight of the mother on body length at birth and at 1, 2, 3, and 6 years of age. Significant sex differences in length were observed at birth and during the first 2 years of postnatal life, but not in the period between 3 and 6 years of age. Socioeconomic status (SES), expressed as a latent variable in the SEM, was not related to body length at birth but was significantly related to body length during infancy and, to a lesser extent, to body length during childhood. Paternal stature was not related to body length at birth and during infancy, but was significantly related to body length from 3 years onwards. Maternal stature was significantly related to body length at birth and at 1 year of age, but not thereafter, while maternal weight was significantly related to body length at birth only. © 1996 Wiley‐Liss, Inc.

Physical growth and development of children, determined by endogenous factors (genetic and paragenetic) is modified by numerous exogenic ones. This affects differentiation of ways of growth in individual children. In order to estimate the individual growth patterns and changes in growth rate as well as differences in growth of boys and girls, one must observe the process of growth of the same children and over a period of many years (longitudinal study). Such longitudinal study is the only way to provide information about the variability of growth and growth velocity at each age. All children were born to parents living in the city of Lublin, Poland, and represented the entire socio-economic strata of the city. Full-term and healthy newborns were examined on the first day of life in obstetrical wards. Follow-up examinations were carried out in the Growth Clinic at regular intervals: monthly during the first year of life, 3-monthly from 1 to 7 years of age, 6-monthly or yearly thereafter until 18 years and, in boys, once more at the age of 21. Anthropometric measurements of 22 morphological traits were taken according to standardised techniques (Martin-Sailer, 1957;Wolanski, 1975).The original sample comprised 578 subjects. However, as in most longitudinal studies, the number of subjects decreased over the long examination period. So, we were left with 290 subjects after 1 year, with 180 after 7 years and with 129 after 18 years.The present study is limited to the analysis of body height in the group of 129 children (70 girls and 59 boys) for whom complete data were available over the whole growth period.Individual growth curves of height for age from 2 to 18 years of all examined children were obtained by fitting the Preece-Baines model 1 (Preece and Baines, 1978) to each child's growth data. The height velocity curves were obtained by calculating the first derivative of the

Aiming at determining the influence of some genetic factors on growth and development, a longitudinal study of 180 children (90 M and 90 F) from the city of Lublin was carried out, with periodical medical examinations and anthropometric measurements from birth to 7 years of age. The parents of each child were also examined. The correlation coefficients between parents and children show that, as regards height, the greatest similarity occurs between mothers and daughters, and a lesser one between fathers and sons. As regards weight, sons are more similar to fathers than daughters to mothers. The relationship between the growth and development of children and the mating type of parents, parental age, and birth order, was also investigated. In negative assortative mating, the children are taller than the children of middle-height parents from positive assortative mating couples. Children (especially daughters) of tall mothers and short fathers grow taller than children of tall fathers and short mothers. Finally, the dependence of growth on parental age and birth order was analysed and the conclusions reached were quite interesting.