Objective: To analyze the regional inequality of height among Chinese Han students aged 7 to 18 years from 1985 to 2014. Methods: The Chinese Han students aged 7 to 18 years with complete basic information and height data from 30 mainland provinces (excluding Hong Kong, Macao, Taiwan and Tibet in China) were extracted as participants from 6 successive cross-sectional surveys of the Chinese National Survey on Student's Constitution and Health (CNSSCH). After excluding extreme and illogical cases, a total of 1 495 182 students were included in the analysis. The data of gross domestic product (GDP) per capita of each province at each survey year were collected from the website of National Bureau of statistics of China. Mann-Kendall trend test was used to analyze the trend of mean height across years. Weighted linear regression model was used to analyze the association between mean height of students aged 7 to18 years and GDP per capita at provincial level. Height difference, height ratio, slope index of inequality (SII) and relative index of inequality (RII) were used to measure the height inequality by gender and age groups. Results: The mean height of Chinese Han students aged 7 to 18 years increased from 144.9 cm in 1985 to 151.8 cm in 2014 (P<0.05). The height difference between urban and rural students in all age groups was reducing (P<0.05). The height difference between urban and rural boys aged 13 to 15 years decreased from 5.3 cm in 1985 to 2.5 cm in 2014, and the difference between urban and rural girls aged 7 to 12 years decreased from 4.6 cm in 1985 to 2.4 cm in 2014. The mean height of students aged 7 to 18 years was positively associated with GDP per capita in all survey years for both genders (P<0.001). Taking Shanghai and Guizhou as the representatives of economically developed and underdeveloped provinces, from 1985 to 2014, the height differences between two provinces were 6.8-9.2 cm, 8.0-12.4 cm and 6.3-8.8 cm for boys aged 7 to 12 years, 13 to 15 years and 16 to 18 years, respectively, and the height ratios were stable at 1.05-1.07, 1.05-1.08 and 1.04-1.05 respectively. From 1985 to 2014, the SII of mean height for boys in three age groups were 4.4-6.2, 4.9-6.7 and 2.5-4.7, respectively. The RII of mean height of boys in three age groups were 1.03-1.05, 1.03-1.04 and 1.01-1.03, respectively. In the same period, the SII of mean height for girls in three age groups were 4.2-6.2, 2.8-4.5 and 2.5-3.9, and the RII were 1.03-1.05, 1.02-1.03 and 1.02, respectively. Conclusion: From 1985 to 2014, the urban-rural inequality of height development among Chinese Han students aged 7 to 18 years was narrowing, but the socio-economic inequality of height persisted and remained at a relatively stable level.
目的： 分析1985—2014年中国7~18岁汉族学生身高发育地区不平等性。 方法： 选取1985—2014年6次全国学生体质与健康调研30个省市（不包括中国香港、澳门、台湾和西藏）基本信息及身高数据完整的7~18岁汉族学生作为研究对象，排除极端值及不合逻辑个案，共纳入1 495 182名学生。通过国家统计局网站收集各省份在调查年度的人均国内生产总值（GDP）数据。采用Mann-Kendall趋势检验分析平均身高值随年份变化的趋势性，采用加权线性回归分析各年度省级层面7~18岁学生平均身高与人均GDP的关联。采用身高差、身高比、不平等斜率指数（SII）和不平等相对指数（RII）衡量不同性别、年龄组身高发育的不平等性。 结果： 中国7~18岁汉族学生平均身高从1985年的144.9 cm上升到2014年的151.8 cm（P<0.05）。各年龄组城乡学生身高差均不断缩小（P<0.05），其中13~15岁组男生城乡身高差从1985年的5.3 cm下降到2014年的2.5 cm，7~12岁组女生城乡身高差从1985年的4.6 cm下降到2014年的2.4 cm。7~18岁汉族男、女学生平均身高与人均GDP均呈正相关（P均<0.001）。以上海和贵州分别作为经济发达和欠发达省份的代表，1985—2014年上海与贵州7~12岁、13~15岁及16~18岁男生的身高差分别为6.8~9.2、8.0~12.4及6.3~8.8 cm，身高比分别稳定在1.05~1.07、1.05~1.08及1.04~1.05。同期3个年龄组男生平均身高的SII分别为4.4~6.2、4.9~6.7及2.5~4.7，RII分别稳定在1.03~1.05、1.03~1.04及1.01~1.03；同期3个年龄组女生SII分别为4.2~6.2、2.8~4.5及2.5~3.9，RII分别为1.03~1.05、1.02~1.03及1.02。 结论： 1985—2014年中国7~18岁汉族学生身高发育的城乡不平等性在缩小，但社会经济不平等性持续存在且处于较稳定水平。.