都市化に伴なう農村児童の季節差発育に関する研究

―身長発育について―

抄録

It is studied in this paper whether the current physical growth rate over four seasons parallels the physical growth rate over four seasons as observed in previous studies. For these purposes, some physical growth traits influenced by urbanization among rural school children were investigated in comparison with urban school children using the longitudinal method.
The results obtained were as follows:
1) Fathers whose only job was farming in the rural sample, were decreasing; conversely farmers having other jobs were increasing. Number of siblings were two in average and families with both parents working increased in rural sample, thus the rural school children were observed being influenced by urbanization remarkably.
2) As for the physical growth rate, the tendency to show remarkable growth in spring was observed to be decreasing, because the season of maximum growth was dispersed among the four seasons, the season depending on age. This is, significantly different physical growth rates were observed in all seasons in addition to spring; therefore growth rate seems to be averaging over seasons as a whole.
3) The change of periodicity in one year was observed in both samples in the process of physical growth on height.
4) But on the other hand, study of the percentage of school children showing maximum growth by seasons revealed that the percentage of those with maximum growth in summer and spring was highest, and those with maximum growth in autumn and winter was lowest. This same seasonal growth was observed in both samples.
5) The two results mentioned at 2) and 4) obtained between the physical growth rate and the percentages of school children showed a possible point of disagreement regarding the maximum growth rate. It should be understood that most of the school children showed maximum growth rate in summer and spring, but the difference of growth rate between these two seasons and the other ones was decreasing.