[Cranial and thoracic circumference as criteria of body development].

The growth of thoracic and neurocranial circumference was studied in 47,099 Czech and Slovak children and adolescents of both sexes, ranging in age from 1 1/2 to 18 years. The data were obtained during our nation-wide studies on the territory of the CSFR in 1987-1988. At the end of the second year of life the values of thoracic circumference were already markedly higher than the values of neurocranial circumference. The characteristics studied show different growth dynamics: The neurocranial circumference increased markedly up to the age of four years, while thoracic circumference showed an onset on intense growth dynamics only at the beginning of the prepubertal period. Throughout the investigated period girls had lower values of neurocranial circumference than boys, yet during the period of puberty their values of thoracic circumference temporarily exceeded the values recorded in boys. After the age of 14 years boys generally had permanently a larger thoracic circumference. Similar to body height and weight both investigated circumferences show an increase in connection with the secular trend. The values of both circumferences are very similar in Czech and Slovak children of the same sex.