中国七岁以下儿童体重、身长/身高和头围的生长标准值及标准化生长曲线

目的 制定中国7岁以下儿童体重、身长/身高和头围的生长标准值及标准化生长曲线.方法 选择"2005年九市7岁以下儿童体格发育调查"中城区儿童为参照人群,采用0～7岁69 760名健康男女儿童的体重、身高(3岁以下为身长)和头围的实际测量值建立数据库.测量数据用标准化的测量方法和质量控制程序获得.采用LMS方法对原始数据进行拟合修匀,通过L、M、S 3个参数计算产生所需要的百分位和标准差单位数值并绘制相应的曲线图.曲线的拟合效果评估采用拟合优度χ2检验.结果 制定出了中国7岁以下男、女童按每月龄的年龄的体重、年龄的身长/身高和年龄的头围第3、10、25、50、75、90及97百分位及-3、-2、-1、0、+1、+2、+3倍标准差单位的生长标准图表(数值表和曲线图).此标准略高于世界卫生组织(WHO)新的5岁以下儿童生长标准.结论 该套生长标准代表了中国营养良好儿童的生长水平,样本量大、具有国家代表性,测量数据精确,研究方法与国际接轨,可作为21世纪中国儿童的生长参照标准在全国范围推广使用.

Growth standardized values and curves based on weight, length/height and head circumference for Chinese children under 7 years of age

Objective To construct the growth standardized data and curves based on weight, length/height, heed circumference for Chinese children under 7 years of age. Methods Random cluster sampling was used. The fourth national growth survey of children under 7 years in the nine cities(Beijing, Harbin, Xi'an, Shanghai, Nanjing, Wuhan, Fuzhou, Guangzbou and Kunming)of China was performed in 2005 and from this survey, data of 69 760 urban healthy boys and girls were used to set up the database for weight-for-age, height-for-age (length was measured for children under 3 years) and head circumference-for-age. Anthropometric data were ascribed to rigorous methods of data collection and standardized procedures across study sites. LMS method based on BOX-COX normal transformation and cubic splines smoothing technique was chosen for fitting the raw data according to study design and data features, and standardized values of any percentile and standard deviation were obtained by the special formulation of L, M and S parameters. Length-for-age and height-for-age standards were constructed by fitting the same model but the final curves reflected the 0.7 cm average difference between these two measurements. A set of systematic diagnostic tools was used to detect possible biases in estimated percentiles or standard deviation curves, including χ2 test, which was used for reference to evaluate to the goodness of fit. Results The 3rd , 10th , 25th, 50th, 75th, 90th ,97th smoothed percentiles and -3, -2, -1,0, +1, +2, +3 SD values and curves of weight-for-age, length/height-for-age and head circumference-for-age for boys and girls aged 0-7 years were made out respectively. The Chinese child growth charts was slightly higher than the WHO child growth standards. Conclusion The newly established growth charts represented the growth level of healthy and well-nourished Chinese children. The sample size was very large and national, the data were high-quality and the smoothing method was internationally accepted. The new Chinese growth charts are recommended as the Chinese child growth standards in 21st century used in China.