Objective: To evaluate the change of prevalence of malnutrition among Chinese primary and secondary school students and to analyze the policy effect during the period of the Program for the Development of Chinese Children 2011-2020 (PDCC 2011-2020).
Methods: The data of Chinese students aged 7 to 18 years were extracted from 8 successive cross-sectional surveys of the Chinese National Survey on Students ' Constitution and Health (CNSSCH) from 1985 to 2019. Malnutrition of students was evaluated according to the screening standard for malnutrition of school-age children and adolescents. The changes of prevalence of malnutrition among primary and secondary school students were described by gender, urban and rural areas, age group and province, from 2010 to 2019. The Joinpoint regression model was used to analyze the trajectory of the prevalence of malnutrition among students aged 7 to 18 years from 1985 to 2019, so as to evaluate the policy effect of the PDCC 2011-2020.
Results: The prevalence of malnutrition among primary and secondary school students in China decreased from 12.7% in 2010 to 8.5% in 2019. The prevalence of malnutrition among boys and girls, urban and rural students, and students of all age groups showed a continuous downward trend (Ptrend < 0.001) from 2010 to 2019. From 2010 to 2019, 27 of the 31 provinces (autonomous regions and municipalities) saw a significant decrease in the prevalence of malnutrition among primary and secondary school students. Joinpoint regression model showed that the prevalence of malnutrition among Chinese primary and secondary school students continued to decline from 1985 to 2019, but 2010 was the turning point in the downward trend. From 1985 to 2010, the prevalence of malnutrition among primary and secondary school students decreased by an average of 2.4% per year (95%CI: 1.9%-2.8%, P < 0.001), and the downward trend accelerated after 2010, with an average annual decline of 4.3% (95%CI: 2.4%-6.2%, P < 0.001).
Conclusion: The prevalence of malnutrition among primary and secondary school students in China continued to decline from 2010 to 2019, achieving the goal of controlling the prevalence of malnutrition among primary and secondary school students in the PDCC 2011-2020. The PDCC 2011-2020 may have played an important role in improving the malnutrition among primary and secondary school students. However, the problem of malnutrition among primary and secondary school students still exists, and it is still necessary to adhere to the coverage and financial support of the nutrition improvement plan in areas with high incidence of malnutrition.
目的: 评估《中国儿童发展纲要(2011—2020年)》(简称2011儿纲)实施期间中小学生营养不良率的变化情况及其政策效应。
方法: 利用1985—2019年8次全国学生体质与健康调研中7~18岁学生的数据，依据《学龄儿童青少年营养不良筛査》判断学生营养不良情况，按性别、城乡、年龄组、省份分层描述中小学生营养不良率在2010—2019年期间的变化情况。利用Joinpoint回归模型对1985—2019年7~18岁学生营养不良率的变化轨迹进行分析，从而评价2011儿纲的政策效应。
结果: 2010—2019年，中国中小学生营养不良率由12.7%下降到8.5%，男女生、城乡学生及各年龄组学生的营养不良率均呈现持续下降趋势(P趋势均 < 0.001)。2010—2019年，31个省(自治区、直辖市)中有27个省份中小学生营养不良率显著下降。Joinpoint回归模型结果显示，1985—2019年，中国中小学生营养不良率持续下降，2010年为下降趋势中的拐点。1985—2010年，中小学生营养不良率平均每年下降2.4%(95%CI: 1.9%~2.8%，P < 0.001)，2010年以后下降趋势加快，平均每年下降4.3%(95%CI: 2.4%~6.2%，P < 0.001)。
结论: 2010—2019年，中国中小学生营养不良率持续下降，实现了2011儿纲中控制营养不良率的目标。2011儿纲的发布可能对于改善中小学生营养不良问题起到了重要的作用，然而目前中小学生营养不良问题仍然存在，仍需加大对于营养不良高发地区的营养改善计划的覆盖范围和财政支持力度。
Keywords: Malnutrition; Policy effect; Primary and secondary school students; Program for the Development of Chinese Children; Trend.