The physical growth of Japanese children from birth to 18 years of age. Cross-sectional percentile growth curve for height and weight.

The purpose of this paper is to set forth the standards of weight and height for the Japanese children and to discuss the mathematical methods utilized for the study. In 1980, Japanese Ministry of Health and Welfare and Ministry of Education conducted a nationwide survey of weight and height in a total of some 680,000 children from birth to 18 years of age. These data were utilized for the present study. In order to draw a mathematically designed smooth curve, we divided the subjects into 4 age groups and expressed each percentile curve of the age range in terms of a polydimensional and polynominal function using the least square method. In comparison with the presently available eye-fit cross-sectional percentile growth curve, our growth curve appears to better simulate physical growth of the contemporary Japanese children.