Secular trends and urban–rural disparities in height of Chinese adolescents aged 18 years from 1985 to 2019

Abstract Objectives To examine the secular trends and urban–rural disparities in height of Chinese adolescents aged 18 years from 1985 to 2019. Methods Data were extracted from the Chinese National Surveys on Students' Constitution and Health from 1985 to 2019, and the heights of a total of 76 554 boys and 75 908 girls aged 18 years were measured. The Mann–Kendall trend test was used to analyze the secular trends in height. Changes in different periods and urban–rural disparities were tested by z ‐tests and calculating the ratios of the coefficient of variation (CV) of height. Results The height of Chinese boys and girls aged 18 years increased from 168.21 and 157.10 cm in 1985 to 172.15 cm and 160.11 cm in 2019, respectively, with a larger increase in rural areas. The secular trends in height were the largest for boys from 1995 to 2005 and for girls from 2014 to 2019, and the same results were observed in urban and rural areas. The urban–rural disparities for boys and girls decreased by 1.79 and 0.91 cm, respectively, with significant decreases for boys in all regions and for girls in the eastern region. The overall CVs of height increased by 0.13% and 0.25% for boys and girls, respectively, with the largest increase among rural girls. Conclusions The height of Chinese adolescents aged 18 years continued to increase between 1985 and 2019. The urban–rural disparities narrowed, and inequalities within rural areas for girls increased.