Weight and body mass index (BMI): current data for Austrian boys and girls aged 4 to under 19 years

Background: BMI reference charts are widely used to diagnose overweight, obesity and underweight in children and adolescents.

Aim: To provide up-to-date national reference values for Austria.

Methods: A cross-sectional sample of over 14?500 children and adolescents (4–19 years) stratified by provinces according to age- and sex-specific population proportions was drawn via schooling institutions (kindergartens, schools and vocational colleges). The generalized additive models for location, scale and shape were used for a flexible estimation of percentile curves.

Results: Austrian boys and girls have higher average weight compared with previous prevalence data. BMI centiles matching BMI values at age 18 years, which are used for defining thinness, overweight and obesity in adults, were calculated. In Austria, using reference values as thresholds, ～18% of boys and 12% of girls are overweight (with thresholds passing through BMI 25.00–29.99?kg/m² in adults) and 5% of boys and 3% of girls are obese (with thresholds passing through BMI ≥30.00?kg/m² in adults).

Conclusion: Overweight and obesity are common in Austria and their prevalence is increasing (using the same IOTF reference for international comparison). Up-to-date national BMI reference values are provided to classify children and adolescents according to the proposed overweight and obesity thresholds.     

Development of body proportions in achondroplasia: Sitting height,leg length,arm span,and foot length

The aims of this study was to construct references for sitting height, leg length, arm span, relative sitting height (sitting height/height), and foot length and to discuss the development for these anthropometric variables in achondroplasia. Sex‐specific references covering ±2 SD are presented for ages 2–20 years. Legs and arms in achondroplasia are already at 2 years of age considerably shorter than in the general population and this deviation increases with age. At adult ages, legs are almost 50% shorter than in the general population and arm span roughly 35% shorter. As sitting height is only mildly affected, relative sitting height position develops far beyond normal ranges. Foot length is also not as affected as limbs.     

Contemporary height,weight and body mass index references for children aged 0 to adulthood in Switzerland compared to the Prader reference,WHO and neighbouring countries*

Abstract

Background: In 2011, WHO growth curves replaced those of Prader and colleagues (First Zurich longitudinal study) in Switzerland.

Aim: To present contemporary height-, weight- and body mass index (BMI)-for-age references reflecting children’s growth in modern Switzerland.

Subjects and methods: Cross-sectional sample comprising 30,141 boys and girls aged 0–20?years measured between 2012 and 2019. Height, weight and BMI reference curves were created using the LMS method. Derived percentiles were compared with those of Prader, WHO and neighbouring countries.

Results: Growth in the first 5?years is almost identical with Prader curves. Thereafter children are taller, yet their final height is only about 1?cm higher. Today’s children, in particular boys, are considerably heavier. In comparison with WHO growth references, Swiss children are taller from the second year until adulthood; the WHO 3rd percentiles lie about 4?cm below those of our updated references. Weight and BMI median percentiles from our sample are similar to those of WHO and higher than the Prader curves. However, the course of the 97th BMI percentile WHO curves extends well below the 97th percentile of the updated Swiss curves.

Conclusion: This study provides contemporary reference data for assessing individual growth based on height, weight and BMI of Swiss children.     

The height increments and BMI values of elite Central European children and youth in the second half of the 19th century

Background: Longitudinal height measurements on children and youth are very rare prior to the 20th century, as are BMI values.

Aim: Growth increments and BMI values were determined among elite (select) Habsburg children and youth in the late 19th century and compared with other extant historical and contemporary data.

Subject and methods: Archival data on height and weight were collected for approximately 3500 students attending Habsburg Military schools. The students were measured once a year for 4 years. Because of the minimum height requirement, truncated regression was used in order to estimate height trends, but standard procedures were used to determine height increments and BMI values.

Results: Heights increased at most 0.9–1.6?cm between the birth cohorts of circa 1870s and 1900. These future officers were about the same size as their counterparts in the USA and France, but smaller than those attending the Royal Military Academy in Sandhurst, England, who were taller and probably the tallest in the world at the time. Height increments were markedly smaller than those experienced by German students in the 18th century after age 15. Central European BMI values were above those obtained in the USA in the 19th century but well below modern values.

Conclusion: Although peak height velocity was experienced as early as ages 13 and 14, the height increments were very small compared even to other historical populations. The military academy selected mainly precocious applicants (with probably larger height increments at younger ages and smaller increments at older ages). BMI values in this sample were well below modern standards, but they were unexpectedly as high as those of contemporary US West Point cadets, a well nourished group. There were significant differences in the height of elites in Central Europe in the 19th century, pointing to substantial socio-economic inequality, but at least the elites were as well nourished as the US population.

Résumé. Arrière plan: Les mesures longitudinales de taille et les valeurs d’IMC avant le 20^ème siècle, sont très rares.

Objectif: Les accroissements de taille et les valeurs d’IMC ont été déterminés parmi l’élite des enfants et des jeunes gens Habsbourg vers la fin du 1ème siècle et sont comparés à d’autres données historiques et contemporaines.

Sujets et méthodes: Des données d’archives sur le poids et la stature ont été rassemblées pour environ 3500 étudiants fréquentant les écoles militaires Habsbourg. Les élèves étaient mesurés une fois par an pendant quatre ans. Du fait de l’existence d’un seuil minimum de stature pour être admis dans ces écoles, les tendances évolutives de la taille on été estimées à l’aide d’une régression tronquée, mais des procédures standard ont été employées pour déterminer les accroissements de stature et les valeurs d’IMC.

Résultats: Les statures se sont accrues au plus de 0,9 à 1,6 cm entre les cohortes de naissance des années 1870 et celle de 1900. Ces futurs officiers avaient à peu près les mêmes tailles que leurs homologues des USA et de France, mais ils étaient plus petits que ceux de l’Académie Militaire Royale de Sandhurst en Angleterre, qui étaient probablement les plus grands du monde à cette époque. Les accroissements de stature étaient nettement plus petits que ceux des étudiants allemands au cours du 18^ème siècle à partir de l’âge de 15 ans. Les valeurs d’IMC de l’Europe Centrale étaient supérieures à celles des USA au 19^ème siècle, mais bien inférieures aux valeurs modernes.

Conclusion: Bien que le pic de croissance ait pris place dès l’âge de 13-14 ans, les accroissements de stature étaient très petits comparés à d’autres populations historiques. L’académie militaire sélectionnait surtout des candidats jeunes (ayant probablement de plus grands accroissements de stature aux jeunes âges et des accroissements plus faibles par la suite). Les valeurs d’IMC de cet échantillon sont très inférieures aux standards modernes, mais de manière inattendue, elles sont aussi élevées que celles des actuels cadets US de West Point, un groupe bien nourri. Il y avait des différences significatives de la stature chez les élites de l’Europe Centrale au cours du 19^ème siècle, indiquant des inégalités socio-économiques substantielles, mais ces élites étaient aussi bien nourries que la population US.

Zusammenfassung. Hintergrund: Es gibt nur wenige longitudinale Körperhöhen- und Body Mass Index (BMI)-Messungen bei Kindern und Jugendlichen vor Beginn des 20. Jahrhunderts.

Ziel: Wachstumsraten und BMI-Werte wurden bei adeligen Kindern und Jugendlichen aus der Habsburg-Dynastie des späten 19. Jahrhunderts erfasst und mit anderen historischen und zeitgenössischen Daten verglichen.

Probanden und Methoden: Es wurden Archivdaten betreffend Körperhöhe und Gewicht von etwa 3500 Kadetten der Habsburger Militärakademien gesammelt. Die Kadetten waren einmal jährlich über einen Zeitraum von 4 Jahren gemessen worden. Aufgrund der Tatsache, dass eine Mindestkörpergröße vorgeschrieben war, wurde mit beschnittenen Regressionen (truncated regression) gearbeitet, um Größentrends zu schätzen, aber es wurden Standardverfahren genutzt, um Wachstumsraten und BMI-Werte zu bestimmen.

Ergebnisse: Die Körperhöhe stieg zwischen den Geburtsjahrgängen der 70iger Jahre des 19. Jahrhunderts und 1900 um maximal 0,9–1,6 cm. Diese zukünftigen Offiziere waren von etwa gleicher Größe wie die aus den USA und Frankreich, aber kleiner als die, die die königliche Militärakademie Sandhurst, England, besuchten, letztere waren noch größer und vermutlich sogar die weltweit Größten zu ihrer Zeit. Die Wachstumsraten waren deutlich kleiner als solche, die man bei über 15-jährigen Deutschen Schülern und Studenten des 18. Jahrhunderts findet. Mitteleuropäische BMI-Werte waren größer als die der USA im 19. Jahrhundert, lagen aber deutlich unter den heutigen Werten.

Zusammenfassung: Obgleich die maximale Wachstumsgeschwindigkeit schon recht früh, d.h. im Alter um 13 bis 14 Jahren, auftrat, waren die Wachstumsraten sogar im Vergleich mit anderen historischen Populationen sehr klein. Die Militärakademie wählte üblicherweise entwicklungsbeschleunigte Bewerber (mit vermutlich größeren Wachstumsraten bei den Jüngeren und kleineren Wachstumsraten bei den Älteren). Die BMI-Werte dieser Stichprobe lagen deutlich unter modernen Standards, aber waren unerwarteterweise so hoch wie bei zeitgenössischen US West Point-Kadetten, einer wohlgenährten Gruppe. Es gab signifikante Unterschiede in der Körperhöhe bei Adeligen aus dem Mitteleuropa des 19. Jahrhunderts, was auf bedeutsame sozioökonomische Unterschiede hinweist, allerdings waren zumindest die Adeligen so gut genährt wie die US-Bevölkerung.

Resumen. Antecedentes: Al igual que sucede con los valores del IMC, las medidas longitudinales de la estatura de los niños y jóvenes son muy escasas antes del siglo XX.

Objetivos: Se han determinado los incrementos del crecimiento y los valores del IMC entre los niños y jóvenes de la elite Habsburgo de finales del siglo XIX, y se han comparado con otros datos históricos y contemporáneos existentes.

Sujetos y Métodos: Se recogieron datos de los archivos sobre la estatura y peso de aproximadamente 3.500 estudiantes que asistían a las escuelas militares de los Habsburgo. Los estudiantes fueron medidos una vez al año durante 4 años. Debido al mínimo de estatura requerido, se utilizó una regresión truncada para estimar las tendencias de la estatura, pero se emplearon procedimientos estándar para determinar los incrementos de la estatura y los valores del IMC.

Resultados: Las estaturas aumentaron no más de 0,9-1,6 cm entre las cohortes de nacimiento de las décadas comprendidas entre 1870 y 1900. Estos futuros oficiales eran aproximadamente de la misma estatura que sus homólogos de Estados Unidos y Francia, pero más bajos que los que asistían a la Academia Militar Real de Sandhurst, Inglaterra, que eran más altos y probablemente los más altos del mundo en aquella época. Los incrementos de la estatura eran marcadamente menores que los experimentados por los estudiantes alemanes durante el siglo XVIII a partir de los 15 años de edad. Los valores del IMC de los centroeuropeos estaban por encima de los obtenidos en los Estados Unidos en el siglo XIX, pero se encontraban muy por debajo de los valores modernos.

Conclusión: Aunque el pico de velocidad estatural tenía lugar a edades tan tempranas como los 13 y 14 años, los incrementos en estatura eran muy pequeños comparados incluso con los de otras poblaciones históricas. La academia militar seleccionaba principalmente a aspirantes precoces (probablemente con mayores incrementos estaturales en las edades más tempranas y menores en edades superiores). Los valores del IMC en esta muestra estaban muy por debajo de los estándares modernos, pero eran sorprendentemente tan altos como los de los cadetes contemporáneos de West Point, en Estados Unidos, un grupo bien alimentado. Durante el siglo XIX existían diferencias significativas en la estatura de las elites centroeuropeas, lo que apunta a una desigualdad socioeconómica substancial, aunque al menos las elites estaban tan bien nutridas como la población de los Estados Unidos de América.     

Leg length,sitting height,and body proportions references for achondroplasia: New tools for monitoring growth

Achondroplasia is the most common form of inherited disproportionate short stature. We report leg length, sitting height, and body proportion curves for achondroplasia. Seven centile format of sitting height, leg length, sitting height/leg length ratio, sitting height/height ratio, and head circumference/height ratio were estimated by the LMS method. The Q‐test was applied to assess the goodness of fit. For comparison, centiles of sitting height and leg length were graphed using Argentine national growth references for achondroplasia and non‐achondroplasia populations. The sample consisted of 342 children with achondroplasia (171 males, 171 females) aged 0–18 years. The median (interquartile range) number of measurements per child was 6 (3, 12) for sitting height and 8 (3, 13) for head circumference. Median leg length increased from 14 cm at age 1 week to 44 and 40 cm (males and females, respectively) in achondroplasia adolescents which is 3.5 cm shorter than non‐achondroplasia children at age 1 week and, 38 cm shorter at adolescence. Median sitting height increased from 34 cm at birth to 86 and 81 in adolescents’ boys and girls respectively, only 5 cm shorter than non‐achondroplasia children. Sitting height/leg length decreased from 2.61 at birth to approximately 1.90 at adolescent. Median head circumference/height ratio decreased from 0.79 at birth to 0.46 at 18 years in both sexes. Growth of lower limbs is affected early in life and becomes more noticeable throughout childhood. The disharmonic growth between the less affected trunk and the severely affected limbs determine body disproportion in achondroplasia.

     

Waist circumference to height ratio predicts inflammatory risk in children

Background: The increase in obesity, especially the increase of visceral fat, has been directly associated with health risk. Additionally, a waist-to-height ratio (WHtR) (0.5) has been proposed as an indicator of early health risk.

Aims: To test the association between anthropometric measurements and inflammatory mRNA expression and to evaluate the effectiveness of WHtR to predict inflammatory risk in children.

Subjects and methods: Anthropometric measurements and fasting blood samples were collected in 94 Brazilian children (46 boys) aged 9–11 years. Children were identified as being at inflammatory risk based on cytokine mRNA expression levels at and above the 75th percentile. Inflammatory cytokine mRNA expression levels were determined through buff-coat using real-time polymerase chain reaction.

Results: Body mass index (BMI), waist circumference (WC) and WHtR showed moderate-to-strong association with inflammatory cytokine mRNA gene expression. WHtR?=?0.51 was the most accurate cut-off point in distinguishing children at inflammatory risk. Compared with children with WHtR <0.51, children with a WHtR ≥0.51 presented an odds ratio of 2.643 (95% CI?=?1.749–3.994) for both diagnosed IL-6 and MCP-1 above the 75th percentile and 2.796 (95% CI?=?1.802–4.338) for TNF-α above the 75th percentile. WHtR?=?0.50 presented the same values of sensitivity and odds ratio and ～7% lower specificity compared to WHtR?=?0.51.

Conclusion: Anthropometric measurements have shown a moderate-to-strong association with the mRNA expression of inflammatory genes and a WHtR of 0.5 could serve as a cut-off point, suggesting increased risk of inflammatory responses.     

Growth in achondroplasia: Development of height,weight, head circumference,and body mass index in a European cohort

As growth references for achondroplasia are limited to reports from United States, Japan, Argentina, and Australia, the aim of this study was to construct growth references for height, weight, head circumference, and body mass index (BMI) from a European cohort of children with achondroplasia and to discuss the development of these anthropometric variables. A mix of cross‐sectional and longitudinal, retrospective, and prospective data from 466 children with achondroplasia and 4,375 measuring occasions were modeled with generalized additive model for location, scale and shape (GAMLSS) to sex‐specific references for ages 0 to 20 years. Loss in height position, that is, reduction in height standard deviation scores, occurred mainly during first 2 years of life while pubertal growth seemed normal if related to adult height. Adult height was 132 cm in boys and 124 cm in girls with a variability comparable to that of the general population and seems to be remarkably similar in most studies of children with achondroplasia. BMI had a syndrome‐specific development that was not comparable to BMI development in the general population. Weight and BMI might be misleading when evaluating, for example, metabolic health in achondroplasia. Head circumference reached adult head size earlier than in the general population. Increased tempo of head circumference growth necessitates thus close clinical follow‐up during first postnatal years.     

Malaysian growth centiles for children under six years old

Background: Growth references are useful for the screening, assessment and monitoring of individual children as well as for evaluating various growth promoting interventions that could possibly affect a child in early life.

Aim: To determine the growth centiles of Malaysian children and to establish contemporary cross-sectional growth reference charts for height and weight from birth to 6 years of age based on a representative sample of children from Malaysia.

Methods: Gender- and age-specific centile curves for height and weight were derived using the Cole’s LMS method. Data for this study were retrieved from Malaysian government health clinics using a two-stage stratified random sampling technique. Assessment of nutritional status was done with the SD scores (Z-scores) of WHO 2006 standards.

Results: Boys were found to be taller and heavier than girls in this study. The median length of Malaysian children was higher than the WHO 2006 standards and CDC 2000 reference. The overall prevalence of stunting and underweight were 8.3% and 9.3%, respectively.

Conclusions: This study presents the first large-scale initiative for local reference charts. The growth reference would enable the growth assessment of a Malaysian child compared to the average growth of children in the country. It is suggested that the use of WHO 2006 Child Growth Standards should be complemented with local reference charts for a more wholesome growth assessment.     

Reference charts of body proportion for Japanese girls and boys

Background:?Data from previous studies provided the mean values of body proportions for each age group of healthy Japanese children, but not the standard curves describing the distribution.

Aim:?The aim of the study was to construct a chart of body proportion of girls and boys in Japan.

Subjects and methods:?About 4% of the nationwide student population in Japan, more than 20?000 children per group of both boys and girls of all ages, was included randomly. The upper/lower ratio (ULR) was calculated from correlation tables containing stature and sitting height data reported in the Statistical Report on School Health and Hygiene. The subischial leg length was calculated by subtracting sitting height from stature.

Results:?The present study showed that Japanese boys (13.5–17.5 years old) were taller and had relatively longer legs than Japanese girls in the same age group, and that the median ULRs of Japanese girls and boys (5.5–17.5 years old) were larger than the average of Caucasian girls and boys reported previously. In boys, the percentile values reached the lowest at 13.5 years, then increased slightly. On the other hand, in girls, the percentile values remained constant after 11.5 years, which is different in boys in the present study and in other Caucasian populations obtained from several studies.

Conclusion:?The new chart provides useful information in the assessment of the body proportions of Japanese children.     

活体切齿至食管齿状线长度与坐高关系的研究

目的　分析坐高与切齿至齿状线长度关系 ,得到由坐高估计切齿至齿状线长度的近似公式 ,为临床相关工作提供参考。方法　对 2 2 3名 (男 162 ,女 61人 )来院进行胃镜检查的非食管疾病患者进行测量。结果　经统计学分析得到不同性别、不同年龄组由坐高估计切齿至齿状线长度的近似公式。结论　所得不同性别、不同年龄组由坐高估计切齿至齿状线长度的近似公式 ,预测效果好     

粤西地区汉族大学生身高与指距的研究

目的 为人类学、法医学及选拔体育人材提供体质学资料。方法 本文采用吴汝康人体测量方法及邵象清人体测量手册的方法，对粤西地区汉族大学生861人（男342人，女519人）身高与指距进行测量分析。结果 粤西地区汉族大学生身高和指距的均值、差值、差值分型、指数等材料相关度较密切，由此推算出回归方程。结论 粤西地区汉族大学生身高、指距测量值及身高指距差的计算和分型均符合国人体型及身高性别差异。     

Use of girth measurements for estimating body volume and body density in Indian girls aged 10–19 years

Summary Mean values and standard deviations of total body volume, body density, height, weight, and a battery of 20 girth measurements of 200 Punjabi girls aged 10–19 years are presented. Selective stepwise multiple regression equations for predicting total body volume and body density from girth measurements are also given for different age groups.Hip girth was the most commonly selected measurement at the first step in most age groups and the values of r between hip girth and total body volume ranged between 0.86–0.96 in different age groups. The values of multiple R between total body volume and a combination of first four selected girth measurements varied from 0.96–0.99 in different age groups.The values of multiple R between body density and a combination of four girth measurements selected up to fourth step ranged between 0.73–0.92 in different age groups.     

1991—2011年广西18～65岁居民身高、体重变化趋势分析

目的了解1991—2011年广西18～65岁居民身高、体重分布情况及其变化趋势。方法利用1991、1993、1997、2000、2004、2006、2009、2011年在广西开展的8次“中国健康与营养调查”追踪调查资料,以广西6市（县）18～65岁城乡居民作为研究对象,共调查7365人次,分析不同年份、不同地区、不同性别以及不同年龄段居民的身高、体重变化趋势。结果广西18-65岁居民身高呈逐年缓慢上升趋势,身高均值从1991年（157．5±8．0）cm,增至2011年的（158．8±8．2）cm,增高了1．2cm,其中城市居民增高2．2cm,农村居民增高0．9cm;男性增高了1．3cm,女性增高了1．1cm。居民体重呈快速增长趋势,体重均值从1991年（51．1±7．7）kg增至2011年的（56．7±10．0）kg,增重了5．6kg,其中城市居民增重5．5kg,农村居民增重5．7kg,城市居民体重均值略高于农村,但农村居民增长幅度大于城市居民;男性增重了6．3kg,女性增重了4．8kg,男性增长速度大于女性。结论1991—2011年间广西居民身高、体重均有不同程度增长．尤其是体重增长速度过快,应引起相关部门的重视,及时采取有效的控制措施,以避免因体重过重而导致超重肥胖呈快速上升趋势。     

Interpreting routine biochemistry in those aged over 65 years: A time for change

In clinical practice, routine biochemistry tests are often performed for diagnostic or screening purposes. We reviewed papers that have reported reference values for people older than 65 years with or without overt health problems. Wider intervals have generally been reported for sodium, potassium, calcium and C-reactive protein (CRP) in the elderly. Higher levels of creatinine and lower levels of total cholesterol (TC) and serum albumin (SA) are observed with ageing. Elderly people have been found to be at greater risk for overt abnormalities in sodium, potassium, creatinine, TC, SA and CRP. The consequences of these abnormalities could be severe. For instance, even mild hyponatremia was associated with increased risk of mortality, disability and myocardial infarction. Mild hypernatremia was associated with severe disability. Mild increases in CRP levels were associated with an increased risk of sarcopenia, disability, cardiovascular disease and cognitive decline. Mild decreases in TC levels were associated with an increased risk of disability or mortality, and mild decreases in SA were associated with an increased risk of mortality, disability, sarcopenia and frailty. Nutritional factors could not wholly explain these effects. Modified biochemical reference values are required for elderly patients, as biochemical results can serve as markers of vulnerability to age-related diseases, linked to metabolism. Careful diagnosis and corrective interventions are needed for patients in this age group.     

新疆锡伯族身高与同身寸长关系的研究

目的 了解锡伯族身高与同身寸长度的关系，为体质人类学填补空白，为生长（年龄）解剖学，法医学提供参考依据。方法 对135名（男59人，女76人）发育正常的成人身高，同身寸进行测量。结果 按年龄、性别分组将得出身高，同身寸长度的基本数据进行统计学处理。结论 得出了新疆锡伯族身高，同身寸长的均值及由同身寸长推测身高的公式及回归方程。     

Body parameters of Czech breastfed children compared to the Czech references and WHO growth standards

Background: The study concerns the comparison of percentile curves of Czech breastfed children with Czech national references from 1991 and 2001 and WHO growth standards. Growth charts of breastfed children demonstrate different curve shapes, especially in the first months of life. Incorrect interpretation of the growth curve could lead to premature introduction of complementary foods or infant formula.

Aim: The comparison of four body parameters of Czech breastfed children with currently used Czech national references and WHO standards in order to recommend that Czech paediatricians use either Czech references or WHO standards in their practice.

Subjects and methods: Nine hundred and sixty breastfed children were included in the study of length-for-age, head circumference-for-age, weight-for-age and weight-for-length parameters. All percentile curves were compared. Values of the 50th percentile expressed in z-scores based on both Czech references and WHO standards were tested.

Results: The study confirmed results of previous surveys documenting that growth of breastfed children is specific. Nevertheless, percentile curves of growth parameters of Czech breastfed children are closer to Czech references than WHO standards.

Conclusions: The Czech national references fulfil the needs of Czech paediatricians (with pointing to specifics of breastfed child growth) and WHO standards are suitable, especially for international comparison.     

Genome-wide linkage screen for stature and body mass index in 3.032 families: evidence for sex- and population-specific genetic effects

Stature (adult body height) and body mass index (BMI) have a strong genetic component explaining observed variation in human populations; however, identifying those genetic components has been extremely challenging. It seems obvious that sample size is a critical determinant for successful identification of quantitative trait loci (QTL) that underlie the genetic architecture of these polygenic traits. The inherent shared environment and known genetic relationships in family studies provide clear advantages for gene mapping over studies utilizing unrelated individuals. To these ends, we combined the genotype and phenotype data from four previously performed family-based genome-wide screens resulting in a sample of 9.371 individuals from 3.032 African-American and European-American families and performed variance-components linkage analyses for stature and BMI. To our knowledge, this study represents the single largest family-based genome-wide linkage scan published for stature and BMI to date. This large study sample allowed us to pursue population- and sex-specific analyses as well. For stature, we found evidence for linkage in previously reported loci on 11q23, 12q12, 15q25 and 18q23, as well as 15q26 and 19q13, which have not been linked to stature previously. For BMI, we found evidence for two loci: one on 7q35 and another on 11q22, both of which have been previously linked to BMI in multiple populations. Our results show both the benefit of (1) combining data to maximize the sample size and (2) minimizing heterogeneity by analyzing subgroups where within-group variation can be reduced and suggest that the latter may be a more successful approach in genetic mapping.     

4—12岁儿童脑地形图正常参考值

目的：研究儿童脑电图的发育。方法：对２２９例４～１２岁正常儿童脑电活动进行计算机分析，统计出该年龄段脑电活动及其快慢频段比的正常参考值。结果：４岁时额部以δ为主，１２岁时以α为主；中央区４岁时以δ为主，８岁时以α为主；顶部４岁时以δ为主，６岁开始以α为主。枕部４～１２岁均以α为主，α能量逐年增高。颞部４岁时以δ为主，８～９岁时以α为主。结论：儿童脑电发育随年龄增长，δ能量百分率减少，α能量百分率增加