[Updated growth standards for Chinese children under 7 years of age].

Objective: To construct growth standards for Chinese children under 7 years of age. Methods: Cross-sectional study design based on national representative data on children's growth and development in 2015 was used. Stratified cluster sampling method was used. A total of 83 628 healthy children aged 0-<7 years from 9 cities, including Beijing, Harbin, Xi'an, Shanghai, Nanjing, Wuhan, Guangzhou, Fuzhou, and Kunming, were investigated from June to November 2015, excluding those with adverse conditions that may impact the establishment of the growth standards. Weight, length (height) and head circumference were measured using unified measurement tools and measurement methods. The Lambda-Mu-Sigma method was employed to establish percentile and standard deviation score reference values of weight-for-age, length (height)-for-age, head circumference-for-age, weight-for-length (height) and body mass index (BMI)-for-age of the study population. The standard deviation score curves of the new-established growth standards were compared with the 2009 reference standards. Results: Reference values of percentile (P3, P10, P25, P50, P75, P90, P97) and standard deviation score (-3, -2, -1, 0,+1,+2,+3) of weight-for-age, length (height)-for-age, head circumference-for-age, weight-for-length (height) and BMI-for-age were obtained. Compared with the 2009 growth standards, the difference of weight at P50 was -0.1-0.4 kg, the difference of length (height) at P50 was 0.1-1.3 cm, the difference of head circumference at P50 was -0.2-0.2 cm, the difference of weight for length (height) at P50 was -0.2-0.5 kg, and the difference of BMI at P50 was -0.2-0.2 kg/m2. The main differences were as follows: weight for girls aged 5.0-<7.0 years was 0.4-0.6 kg higher at +2 s, height for boys and girls aged 2.0-<7.0 years was 0.4-1.4 cm higher at -2 s, and BMI for boys and girls aged 5.0-<7.0 years was 0.1-0.3 kg/m2 higher at +2 s than the 2009 reference standards. Conclusion: The newly established growth standards for Chinese children under 7 years of age that have achieved a minor revision to the 2009 reference standards, are recommended for nationwide use in growth monitoring and nutritional assessment.目的： 建立中国7岁以下儿童的生长标准值。 方法： 横断面研究基于2015年儿童生长发育国家调查数据，采用分层随机整群抽样方法，于2015年6—11月在北京、哈尔滨、西安、上海、南京、武汉、广州、福州、昆明9个城市调查7岁以下健康儿童83 628名。采用统一的测量工具按照统一的测量方法获得儿童体重、身长（身高）和头围的测量值。采用基于偏度、位置和变异的曲线平滑方法建立7岁以下男、女童年龄的体重、年龄的身长（身高）、年龄的头围、身长（身高）的体重、年龄的体质指数的生长曲线模型。将新建立的生长标准各指标的标准差单位曲线与2009年参照标准进行比较。 结果： 制订出7岁以下男、女童年龄的体重、年龄的身长（身高）、年龄的头围、身长（身高）的体重、年龄的体质指数的百分位数（P3、P10、P25、P50、P75、P90、P97）和标准差单位（-3、-2、-1、0、+1、+2、+3）标准值。与2009年参照标准相比，体重在P50上差值为-0.1~0.4 kg，身长（身高）在P50上差值为0.1~1.3 cm，头围在P50上差值为-0.2~0.2 cm，身长（身高）的体重在P50上差值为-0.2~0.5 kg，体质指数在P50上差值为-0.2~0.2 kg/m2，主要差别表现在：5.0~<7.0岁女体重在+2 s上高0.4~0.6 kg，2.0~<7.0岁男、女身高在-2 s上高0.4~1.4 cm，5.0~<7.0岁男、女体质指数在+2 s上高0.1~0.3 kg/m2。 结论： 新建立中国7岁以下儿童生长标准，实现了对2009年参照标准的微小修订，可在全国范围内用于儿童生长监测与营养评估。.