WHO Child Growth Standards based on length/height, weight and age

Aim: To describe the methods used to construct the WHO Child Growth Standards based on length/height, weight and age, and to present resulting growth charts. Methods: The WHO Child Growth Standards were derived from an international sample of healthy breastfed infants and young children raised in environments that do not constrain growth. Rigorous methods of data collection and standardized procedures across study sites yielded very high-quality data. The generation of the standards followed methodical, state-of-the-art statistical methodologies. The Box-Cox power exponential (BCPE) method, with curve smoothing by cubic splines, was used to construct the curves. The BCPE accommodates various kinds of distributions, from normal to skewed or kurtotic, as necessary. A set of diagnostic tools was used to detect possible biases in estimated percentiles or z-score curves. Results: There was wide variability in the degrees of freedom required for the cubic splines to achieve the best model. Except for length/height-for-age, which followed a normal distribution, all other standards needed to model skewness but not kurtosis. Length-for-age and height-for-age standards were constructed by fitting a unique model that reflected the 0.7-cm average difference between these two measurements. The concordance between smoothed percentile curves and empirical percentiles was excellent and free of bias. Percentiles and z-score curves for boys and girls aged 0–60 mo were generated for weight-for-age, length/height-for-age, weight-for-length/height (45 to 110 cm and 65 to 120 cm, respectively) and body mass index-for-age.
Conclusion: The WHO Child Growth Standards depict normal growth under optimal environmental conditions and can be used to assess children everywhere, regardless of ethnicity, socio-economic status and type of feeding.     

Secular changes in body height and weight in children and adolescents in Poznan,Poland, between 1880 and 2000

AIM: A secular trend in body height and weight is well documented. The first observations concerning this phenomenon in Poland were made at the end of the 19th century. The aim of this study was to assess changes in body height and weight during the 20th century, with special emphasis on the last decade. METHODS: The results of body height and weight measurements obtained in eight subsequent surveys (1880-1886, 1922-1927, 1946-1950, 1960-1961, 1970-1971, 1980-1981, 1990-1991 and 1999-2000) were included in the analysis. Mean values were compared and differences between the surveys were analysed. RESULTS: In general, in the 20th century, children grew taller and heavier and reached final body height and weight more rapidly. The biggest differences in body height and weight in the 20th century, observed at growth spurt, were about 17 cm and 11 kg, respectively, for boys, and 13 cm and 13 kg for girls. The magnitude of secular changes in body height and weight in the 20th century was not stable. There were periods of increased and decreased intensity of acceleration of physical development (the 1950s and 1970s, and the 1960s and 1980s, respectively), as well as a period of deceleration (the 1940s). In the last decade, the tendency has been towards deceleration in most age groups studied. CONCLUSION: The acceleration of physical development in children in Poznan has now ceased.     

Quantifying the relationships of blood pressure with weight, height and body mass index in Chinese children and adolescents

Aim: The aim of this study was to quantify the relationships of height, weight and body mass index (BMI) with blood pressure (BP) levels in Chinese children and adolescents. Methods: Height, weight, BMI and BP measurements were obtained from a nationally representative sample of 231 227 children aged 7–18 years. Body size measurements were converted to age‐ and sex‐specific standard deviation (SD) scores. The relationships between body size and BP measurements were assessed using linear regression analysis. Results: All body size measurements were significantly associated with BP levels. Systolic BP increased 4.14, 3.70 and 2.88 mmHg in boys and 2.98, 2.63 and 1.87 mmHg in girls, corresponding to 1 SD increase in weight, BMI and height, respectively. A similar pattern was also observed for diastolic BP. After adjustment for height, systolic BP increased substantially with increasing weight (3.96 mmHg/SD increase for boys and 2.92 mmHg for girls). With adjustment for weight, systolic BP increased slightly with 1 SD increase in height (0.27 mmHg for boys and 0.10 mmHg for girls). The strength of the association between a body size measurement and BP varied among different ages, peaked at 10–11 years in girls and around 12–14 years in boys. Conclusions: Weight is the most powerful driving force of BP in children and adolescents, followed by BMI and height. Height has little impact on BP in children with a given weight, while weight has considerable impact on BP in children with a given height.     

Effects of giardiasis on school success, weight and height indices of primary school children in Turkey

BACKGROUND: Giardia intestinalis, the most common parasite in the world, causes several adverse effects on school children, with the prevalence rate ranging between 7.3% and 28% (mean 13.8%) in Turkey. The aim of the present study was to investigate possible adverse effects of G. intestinalis on success at school, and the mean weight and height of primary school children in Sivas, Turkey. METHODS: Five primary schools from central Sivas, Turkey, had a number of students from different socioeconomic conditions and regions. The stool specimens were examined by light microscopy for giardiasis using saline-Lugol and/or zinc sulfate flotation method. Three groups in the present study include the symptomatic giardiasis group (SG), which included children with giardiasis along with abdominal pain and/or diarrhea, the asymptomatic giardiasis group (ASG) without any symptom and the non-parasitic (NPG) group without any parasites. RESULTS: While 599 (34.6%) out of 1730 children were parasitic, 192 (11.1%) had only G. intestinalis. Ninety-eight (5.7%) of 192 were SG (with diarrhea and/or abdominal pain and 94 (5.4%) were ASG. The weights and heights were lower in the children with giardiasis than the children without any parasite. There was a significant difference between the giardiasis group and NPG when the numbers of persons living in the house were compared. While there were no significant difference between the giardiasis group and NPG when the sexes were compared, success at school and economical levels were found to be significantly different between these groups. CONCLUSION: There was a higher prevalence of giardiasis in primary school children and their physical and mental conditions were affected adversely. Giardia infections in particular have adverse effects on success at school.     

Differences in height and weight between children living in neighbourhoods of different socioeconomic status

Data on height, weight and pubertal development of 8596 Dutch children were taken to study differences in health status between children living in neighbourhoods of different socioeconomic level in Rotterdam. The data were obtained during regular school medical examinations of children aged 5, 7, 11 and 14 years. Children living in poor neighbourhoods appeared to be shorter than children living in rich neighbourhoods. Overweight appeared to be more prevalent amongst children living in poorer neighbourhoods.     

Turner's syndrome in Italy: familial characteristics, neonatal data, standards for birth weight and for height and weight from infancy to adulthood

In 1990, the Italian Study Group for Turner's Syndrome (ISGTS) undertook a nationwide survey, involving the retrospective collection of cross-sectional data and longitudinal growth profiles of 772 girls with Turner's syndrome born between 1950 and 1990. The study was carried out in 29 pediatric endocrinological centers. In this first report, the familial characteristics and neonatal data of Turner girls are described, compared to those of the general population, and related to postnatal somatic development. Furthermore, charts for birth weight and growth standards for height and weight from infancy to adulthood are presented (these are the first charts based on a large sample from the Mediterranean area). The main findings were: (1) incidence of Turner births increases with parental age or parity; (2) most of the neonates are small for dates; (3) girls with normal birth weight tend to be both taller and heavier than girls with low birth weight during the whole growth period; and (4) a 10-cm difference in midparental height leads to a 6.5-cm difference in adult stature.     

中国儿童身高与体重的生长模式及简单数学模型的建立

目的 探讨中国儿童身高、体重生长规律及反映规律的简单数学模型.方法 采用"2005年九市7岁以下儿童体格发育调查"及"2005年中国学生体质与健康调研"所获得的0～18岁儿童的身高、体重数据.0～6岁身高和体重曲线采用LMS法拟合,6～18岁数据采用三次样条函数平滑修匀和修正LMS法转换.生长速度根据生长曲线修匀后获得的数值计算产生.1～10岁儿童身高和体重的简单线性模型采用修匀后生长数据建立.结果 (1)我国儿童出生身长约50 cm,3、6、12、24月龄时约61、67、76、88 cm.2～10岁身高增长较为稳定,平均每年增长约6～7 cm.约3岁半和12岁时的身高分别达到出生时2倍和3倍.2～10岁估算公式:身高(cm)=年龄(岁)×6.5+76.(2)出生体重约3.3 kg.出生后第一个3个月生长速度最快,平均每月体重增加约1.0～1.1 kg;第二个3个月减慢一半,约0.5～0.6 kg,出生后第一年的后6个月又减慢一半,约0.25～0.30 kg.约3、12、24月龄时体重达到出生时的2、3、4倍.1～6岁、7～10岁体重基本呈匀速增加,平均每年分别增长2 kg和3 kg左右.1～6岁估算公式:体重(kg)=年龄(岁)×2+8,7～10岁:体重(kg)=年龄(岁)×3+2.结论 针对临床实践的需要,总结不同年龄阶段身高、体重的增长规律,提供了0～18岁儿童身高和体重的生长速度参考值,同时对1～10岁儿童身高和体重估算公式进行修订.     

Standards for height, weight and head circumference from one month to six years based on Stockholm children born in 1980

Growth data on height, weight and head circumference were collected from Stockholm children from one month to six years of age, born in 1980, and representing all socio-economic groups. The sample consisted of 2471 children (1264 boys and 1207 girls), most of whom were measured on 10–15 occasions. From these measurements centile standards were constructed using a statistical technique which separates between-individual and within-individual variation, since only the former is appropriate to distance standards. Compared to former Swedish standards the present heights and weights were similar up to 2.0 years of age but thereafter considerably greater. Head circumference was larger throughout, perhaps due to a difference in measurement technique.     

Reference values for height and weight in Prader-Willi syndrome based on 315 patients

The spontaneous growth of 315 patients (109 girls and 208 boys) with Prader-Willi syndrome (PWS) was analysed in a mixed longitudinal and cross-sectional manner. 33 patients were seen in the department between 1970 and 1994; height and weight of 76 patients from Germany were evaluated by means of a questionnaire with detailed measuring instructions, and 206 definite cases were added from the literature. Mean (±SD) length of newborn babies with PWS was 50.2 ± 2.8 cm (145 boys) and 48.9 ± 3.3 cm (79 girls). Mean weight at birth was 2945 ± 570 g in boys and 2782 ± 594 g in girls. During the 1st year, the children's growth was nearly normal, thereafter short stature was present in approximately 50% of PWS patients. Between 3 and 13 years of age, the 50th percentile for height in PWS is roughly identical with the 3rd percentile in healthy controls. Body weight was normal for all boys and girls during the first 2 years. Thereafter, a rapid weight gain occurred; after an age of 10 years weight-for-height index in nearly all patients exceeded the normal range. The extent of pubertal growth was reduced for the group. Mean adult height was 161.6 ± 8.1 cm (23 males) and 150.2 ± 5.5 cm (21 females). Head circumference for age was normal for boys and girls. Conclusion Reference data on spontaneous development of growth and weight gain of children with Prader-Willi syndrome are described allowing a better counselling of patients and parents. Received: 2 September 1997 / Accepted in revised form: 8 December 1997     

Weight, height and weight for height in 6–7-year-old children I. Relationship with demographic variables

Relationships between weight, height and weight for height at 6–7 years of age and a number of demographic variables have been studied in data from Infant Welfare Centre and school medical records. In both boys and girls height and weight were significantly related to birthweight. After allowing for birthweight and age no significant relationships were found in either boys or girls between height and any of the demographic variables. However, body mass index differed significantly according to birth order, the number of children in the family and the parents country of birth. No associations were observed between anthropometric measures at 6–7 years and paternal occupational status, maternal age and the number of younger siblings. Comparison of the study group with reference values from America and Australia provided no support for the view that one of these reference standards is more appropriate than the other for assessment of growth in Australian children.     

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.     

中国0～18岁儿童、青少年身高、体重的标准化生长曲线

目的 研究制定中国0～18岁儿童、青少年身高、体重的生长参照值及标准化生长曲线,供儿科临床及预防保健工作使用.方法 采用"2005年中国九市7岁以下儿童体格发育调查"及"2005年中国学生体质健康调研"中九省市94 302名0～19岁(差1天未满19岁)城区健康儿童青少年的身高(3岁以下测量身长)、体重测量数据,应用LMS方法对数据进行拟合修匀,获得所需要的百分位和标准差单位(Z分值)数值并绘制相应的曲线图.结果 制定出0～18岁男、女儿童各自的年龄的体重、年龄的身高第3、10、25、50、75、90及97百分位及-3、-2、-1、0、+1、+2、+3倍标准差(SD)单位曲线图.与世界卫生组织(WHO)新的生长标准及美国疾病预防控制中心(CDC)2000年(CDC2000)标准进行比较,三者之间存在差异.男童15岁、女童13岁之前,中国儿童身高略高于美国及WHO标准,之后逐渐低于美国及WHO标准,18岁时男童身高低于美国3.5 cm,女童低于美国2.5 cm;体重在学龄期后差异明显,18岁时中国男童低于美国平均约5.9 kg,女童差别更大,8～18岁间差值约4.1～20.5 kg.结论 该套身高、体重标准图表具有国家代表性、年龄完整,可作为中国儿童青少年的生长参照标准在儿科临床及公共卫生领域中使用,有利于生长异常的早期识别、疾病的诊断以及治疗效果的评价.     

Predictors of self-reported problem behaviours in Turkish immigrant and Dutch adolescents in the Netherlands

BACKGROUND: Although many studies have compared psychopathology in different cultures, not much is known about factors that contribute to the observed differences. METHODS: We compared self-reported emotional and behavioural problems in 363 Turkish immigrant and 1098 Dutch adolescents in the Netherlands and we evaluated the contribution of adolescent, parent, family and stress-related factors to the observed ethnic differences. Data were drawn from the Dutch version of the Youth Self-Report (YSR), as well as from Dutch and Turkish parental questionnaires. RESULTS: Turkish girls scored higher on four of the eight YSR syndrome-scales, on the Internalising broadband scale and on total problems than Dutch girls. Turkish boys scored higher on three syndrome scales and on the Internalising scale, but scored less on Delinquent Behaviour than their Dutch peers. Ethnic differences for both sexes were most pronounced on the Withdrawn and Anxious/Depressed scales. Socio-economic measures, in particular education of the parents, contributed most to the explanation of ethnic differences on the Somatic Complaints scale for girls and Social Problem and Internalising scales for boys. On most scales, however, ethnic differences could not be explained by other factors. The distribution of some factors appeared to be more favourable (i.e., less frequent) for Turkish than for Dutch youths, such as referral of family members to mental health services. CONCLUSIONS: Low educational levels of the parents play an important, yet not an exclusive role in explaining cross-cultural differences in emotional and behavioural problems in adolescents. In particular, differences in Withdrawn and Anxious/Depressed behaviour could not be explained by non-cultural factors. This study offers starting-points for future research on cultural-specific predictors of psychopathology in immigrants.     

Slowing of growth in height and weight on stimulants: a characteristic pattern

OBJECTIVE: The aims of the present study were to describe the growth pattern of children starting stimulant medication and to analyse the changes over time in height, weight and height velocity in a cohort of treated patients. METHODS: Retrospective review of growth data from files of all newly treated patients with attention-deficit/hyperactivity disorder in one paediatric practice. Forty-four boys and seven girls were treated for 6-42 months with either dexam-phetamine (n = 32) or methylphenidate (n = 19). RESULTS: During the first 6 months on stimulant medication 44 children (86%) had a height velocity below the age-corrected mean and there was weight loss in 39 (76%). The height and weight standard deviation score (SDS) showed a progressive decline that was statistically significant after 6 and 18 months (P < 0.001, paired t-test). The height velocity was significantly attenuated for the first 30 months (P < 0.01), being lowest during the first 6 months. The mean height deficit during the first 2 years was approximately 1 cm/year. The change in weight SDS was 2.4 times the change in height SDS after 30 months on treatment with a significant correlation (Pearson's correlation coefficient r = 0.88, P < 0.001). CONCLUSIONS: Stimulant medication is associated with a decrease in height and weight SDS during the first 6-30 months with a characteristic pattern on the growth chart.     

Influence of treatment modalities on body weight in acute lymphoblastic leukemia

Weight for height of 92 patients (51 girls and 41 boys) treated for acute lymphoblastic leukemia (ALL) was evaluated in a longitudinal study. Fifty-four patients received cranial irradiation (CI) with a dose of 18 or 24 Gy and 38 patients did not receive CI. Seventy-seven patients were treated according to a normal-risk protocol and 15 patients received more intensive chemotherapy according to a high-risk protocol. In most of the patients the duration of follow-up was 12 years for irradiated patients and 4.5 years for the nonirradiated patients. Thirty of 92 patients were treated according to a protocol without CI, but with a difference in the use of corticosteroids: 19 patients received dexamethasone during the remission-induction and maintenance treatment and 11 patients received prednisone. The influence of dexamethasone vs. prednisone, sex, CI and high-dose vs. low-dose chemotherapy on weight for height was evaluated. Patients who received dexamethasone showed a significant increase in weight for height immediately after the start of therapy. In patients who received CI, weight for height significantly increased after the first year of treatment. The overweight in these patients persisted during the whole follow-up period. The weight for height of patients treated with prednisone and of patients who did not receive CI was below the mean of the normal population during treatment but was not different from normal after cessation of therapy. No difference in weight gain was seen between boys and girls and between patients who were treated with high vs. normal-risk protocols. © 1996 Wiley-Liss, Inc.     

Prediction of height achievement at five years of age in children born very preterm or with very low birth weight: continuation of catch-up growth after two years of age

To predict height at five years in a cohort of 565 very preterm and/or very low-birth-weight children, hypothesized growth determinants were subjected to discriminant analysis. Many neonatal parameters were not significantly associated with short stature at five years of age. A correct classification of stature (smaller/larger than the 10th percentile at five years of age) could be obtained in 85% of children, using the following variables: height at two years of age; total (or mid) parental height; parental level of education; length at one year of age; hypertension during pregnancy; sex; weight at two years of age; length percentile at one year of age. However, when compared to actual longitudinal data, the false-positive rate was 37%. The survey also demonstrated the continuing catch-up growth in very preterm and very low-birth-weight infants after two years of age.     

Executive function outcome in preterm adolescents

Preterm birth (PT) and low birthweight (LBW) are risk factors for cognitive, academic, and behavioral difficulties. Executive functioning, which is an umbrella term encompassing higher-order problem-solving and goal-oriented abilities, may help to understand these impairments. This review article examines executive functioning in PT and LBW children, with a specific focus on adolescence and the functional consequences of executive dysfunction in this age group. We have focused on adolescence as it is a critical period for brain, cognitive and social–emotional development, and a period of increased autonomy, independence and reliance on executive functioning. While more longitudinal research is required, there is evidence demonstrating that the PT/LBW population is at increased risk for impairments across all executive domains. Emerging evidence also suggests that executive dysfunction may partly explain poorer academic and social–emotional competence in PT/LBW adolescents. In conclusion, PT/LBW adolescents exhibit poorer executive functioning, and close surveillance is recommended for high-risk individuals.     

Early rapid weight gain and current overweight in relation to asthma in adolescents born with very low birth weight

Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.