ISSN:1042-0533    

DOI:10.1002/ajhb.1310010202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractMeasures of mature heights of the second generation of longitudinal subjects in the Fels Institute growth study are now becoming available. When augmented by the heights of the parents who enrolled the first‐generation children, these families provide three‐generation data for mature height. Heights of the first‐generation spouses are also available. The successive generations correspond approximately to the following birth cohorts: 1886–1920, 1921–1949, and 1950–1968. Also available in the Fels data are heights for two‐generation families with parents and offspring in successive cohorts. In the three‐generation families, the mean increases (cm) for 34 grandmothers, mothers, and daughters were 2.99 and 2.77, both significant withP<0.01; for 14 grandfathers, fathers and sons, 3.15 and 3.63, the latter significant withP<0.05. In the first and second cohort two‐generation families, the mean increase for 67 mothers and daughters was 4.01 (P<0.01); for 62 fathers and sons, 3.84 (P<0.01). In the second and third cohorts, the corresponding figures for 53 and 52 pairs were 3.00 and 4.36, bothP<0.01. In every case, the change in the rate of increase between the first and second generation cohort, and that between the second and third, was not statistically significant. There is no clear evidence that the secular increase in height is decreasing in these families. The finding must be qualified, however, by the observation that most of the first‐generation subjects grew to maturity during the Great Depression, when nutrition may have suffered relative to that of the post‐World War II years of the maturing second generation. Study of a third generation of Fels subjects may be necessary before a decrease in the secular trend becomes e

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractA generalized procedure, elliptical Fourier analysis, for accurately characterizing the shape of complex morphological forms of the type commonly encountered in the biological sciences, is described. Elliptical Fourier functions are derived as a parametric formulation from conventional Fourier analysis, i.e., as a pair of equations that are functions of a third variable. The use of elliptical Fourier functions circumvents three restrictions that have limited conventional Fourier analysis to certain classes of shapes. These restrictions are (1) equal divisions over the interval or period; (2) dependency on the coordinate system, i.e., conventional Fourier functions are not “coordinate free”; and (3) the presence of shapes with outlines that curve back on themselves, a common occurrence. These three limitations are effectively removed with the utilization of elliptical Fourier functions, facilitating the analysis of a much larger class of two‐dimensional

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractResistant delineation, a technique adapted from exploratory data analysis (Tukey, Exploratory Data Analysis, 1977), was applied to smooth age‐specific percentiles for triceps skinfold thickness across ages from 1 to 20 years. Row percentiles were transformed to logarithms to promote symmetry and to render variability more nearly homogeneous across ages. The delineation involved smoothing resistantly the sequences of age‐specific log medians and the sequence of age‐specific positive differences between the “4253H, twice” (Velleman, J. Am. Statist. Assoc.,75:609–615, 1980). The delineation concluded by recombining these smoothed sequences to obtain smoothed percentiles in the log scale. Finally, the logarithmic transformation was reversed, yielding the smoothed age‐specific percentiles. Comparisons of smoothed results from resistant, delineation with the original data indicated a satisfactory fit. Comparisons with published smoothed percentiles, obtained from the same data by a cubic‐spline procedure, showed that the resistant delineation captured the structure of the raw data better than the cubic‐spline procedure. The resistant delineation procedure makes few assumptions of the underlying data, it ensures a proper order relationship among the smoothed percentiles, it is relatively insensitive to isolated unusual data, and it is available in a common

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe FELS method of assessing the skeletal maturity of the hand‐wrist differs from the Greulich‐Pyle and Tanner‐Whitehouse methods in the observations made, the provision of a range of shapes to which maturity indicator grades can be assigned and in the statistical methods used to construct the scale of skeletal maturity. The FELS method for the hand‐wrist was developed using 13,823 serial radiographs of the left hand‐wrist of boys and girls in the Fels Longitudinal Study. One hundred‐thirty possible indicators were originally identified. Eighty‐five graded and 13 metric indicators were selected on the basis of an indicator's ability to discriminate between children at the same chronological age, its universal appearance, reliability, validity, and completeness. The subset of FEELS maturity indicators assessed at a chronological age are analyzed with a microcomputer program that provides the skeletal age and the standard error of the estimate for that skeletal age. Comparison among hand‐wrist skeletal age assessments for children in the Fels Longitudinal Study by the FELS, Greulich‐Pyle, and Tanner‐Whitehouse methods indicate that the FELS method is the more appropriate method for the present population of Uni

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractGiven a number of developing aspects of the skeletal system that may be used as indicators of maturity, some combination rule is required to produce a single numerical description of skeletal maturity from data on several such indicators. In the RWT system for estimation of skeletal maturity from indicators in the knee, a nonlinear statistical model for graded data is used for this purpose. In the application of a similar model in the FELS system for the hand‐wrist, the estimation procedure was extended to include continuous as well as graded indicators. This paper describes the statistical estimation procedure used, with illustrations drawn from the hand‐wrist sys

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractWeight, stature, bicondylar and biepicondylar breadths, estimated midarm muscle circumference, grip strength, and skeletal maturity were compared in 111 obese Black and 120 obese White children, 6 through 12 years of age. The children were classified as obese by the triceps skinfold (TSF), body mass index (BMI), or both, and were labeled, respectively as TSF Obese, BMI Obese, and BMI+TSF Obese. The anthropmetric dimensions, including grip strength, were transformed to z scores on the basis of age‐, sex‐, and race‐specific means and standard deviations for a mixed longitudinal sample of children among whom the obese children were indentified. Skeletal maturityu was expressed as the diference between skeletal age (Tanner‐Whitehouse II RUS method) and chronological age. Within each racial group, BMI+TSF Obese are heavier and taller, have larger extremity bone widths, have larger estimated midarm musculature, are stronger, and are more advanced in skeletal maturity than TSF Obese and average nonobese children. Although the number of children classified as BMI Obese is small, their apparently unique characteristic is an especially large estimated midarm muscle circumference compared to other obese c

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThis paper estimates the prevalence of obesity in 6–8‐year‐old children, 13–15‐year‐old youth, and 18–19‐old adults by using skinfold data of the National Nutrition and Health Examination Survey. Obesity is defined as above 25% fat in males and above 32% fat in females. Skinfold equations used to estimate the fat cotent at each age were based on a multicompontent approach that used body density, body water, and bone mineral. The prevalence of obesity in the U.S. population was found to be much lower in children than in youth and young adults and to increase from 1 in 20 in childhood to 1 in

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractRecently, two new methods (total body electrical conductivity [TOBEC] and bioelectrical impedance analysis [BIA]) have become available for the rapid, safe, and convenient estimation of total body water in hospital patients. Despite these clear advantages, the clinical usefulness of the TOBEC and BIA methods in patient diagnosis and care is likely to be restricted by illness‐related changes in the hydration of the lean body and in the distribution of water between the intracellular and extracellular water compartments. If these methods can be refined so as to permit their measurement of extracellular water as rapidly as they now measure total body water, the ability of clinicians to assess and monitor the nutritional and metabolic status of their hospital patients will be greatly enhance

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractActivity level and energy intake were estimated from 3‐day records, including a weekend day, in parents and children from families of French descent. Subcutaneous fat from the summation of six skinfolds, fasting serum triglycerides, total and high‐density lipoprotein cholesterol, and submaximal power output (PWC150) derived from a cycle ergometer test also were determined in these subjects. Dependent variables were normalized through log10or squre‐root transformation, and scores were adjusted by generation for the effects of age and gender. Correlations with residual scores were performed with pairs of natural parents and child (N ≧ 1057) and pairs of foster parent and adopted child (N ≧ 283). Coefficients were generally little affected by statistical control over current activity level and energy intake. Pairs of biological relatives were classified as either very similar (25% of pairs) or very dissimilar (25% of pairs) in terms of energy intake or activity level. Correlations revealed that similarity or discordance in energy intake or activity level had only a slight effect on parent‐child resemblance. In addition, duration of cohabitation had little influence on parent‐child covariation. It was concluded that parent‐child resemblance in subcutaneous fat, work capacity, and blood lipids are not significantly affected by current patterns of energy intake, activity level, or duration

ISSN:1042-0533    

DOI:10.1002/ajhb.1310010211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY