Abstract
Background There are annual reports, accumulated over more than 50 years, called the Statistical Survey on School Health, concerning the physical development of Japanese school children. In order to clarify the local differences in Japanese children's BMI and its change over time, we investigated height and weight data of those aged 5 to 17 over a span of 55 years (from 1948 to 2003).
Methods Using the national average and 47 prefectural averages of height and weight data, the BMI was calculated for each age in each year. Then, the BMI difference of prefectural averages compared to the national average was calculated respectively and assigned a color in accordance with the value of the BMI difference. A BMI cross-sectional map of each prefecture was constructed to visualize the physical changes.
Results Excess BW of children is more prominent in northeastern compared to southwestern Japan.
Conclusion We analyzed the Statistical Survey on School Health conducted over a period of 55 years using BMI cross-sectional analysis to estimate Japanese children's physical development. Our results showed that excess BW is more prominent in northeastern compared to southwestern Japan. We suggest that children's physical development exhibits local differences and is affected by regional factors.
