Research by members of the International Society for the Study of Human Growth and Clinical Auxology

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Age at menarche and chemical exposure

Lawrence M. Schell. ABSTRACT (partial): Context: Humans are now exposed to a multitude of chemicals throughout the life course, some of which may affect growth and development owing to their endocrine-like activity.

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From growth charts to growth status: How concepts of optimal growth and tempo influence the interpretation of growth measurements

Babette S. Zemel. ABSTRACT (partial): Growth measurements are largely uninterpretable without comparison to a growth chart. Consequently, the characteristics of a growth chart become an integral component of the interpretation of growth measurements. The concepts of optimal growth and tempo are well recognised by auxologists, yet their implications for interpretation of growth measurements remain problematic.

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Smoothing reference centile curves: The LMS method and penalized likelihood

TJ Cole. ABSTRACT (partial): Reference centile curves show the distribution of a measurement as it changes according to some covariate, often age. The LMS method summarizes the changing distribution by three curves representing the median, coefficient of variation and skewness, the latter expressed as a Box-Cox power.

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SITAR—a useful instrument for growth curve analysis

TJ Cole. ABSTRACT (partial): Background: Growth curve analysis is a statistical issue in life course epidemi- ology. Height in puberty involves a growth spurt, the timing and intensity of which varies between individuals. Such data can be summarized with individual Preece–Baines (PB) curves, and their five parameters then related to earlier exposures or later outcomes. But it involves fitting many curves

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Sample size and sample composition for constructing growth reference centiles

TJ Cole. ABSTRACT (partial): Growth reference centile charts are widely used in child health to assess weight, height and other age-varying measure- ments. The centiles are easy to construct from reference data, using the LMS method or GAMLSS (Generalised Additive Models for Location Scale and Shape). However, there is as yet no clear guidance on how to design such studies, and in particular how many reference data to collect, and this has led to study sizes varying widely.

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