Related Experiment Videos
Analysis of linear growth using a mathematical model. II. From 3 to 21 years of age
J Karlberg1, J G Fryer, I Engström
1Department of Anatomy, University of Gothenburg, Sweden.
Insights
The ICP growth model analyzes healthy child growth, including puberty variations. It offers new standards for evaluating individual growth patterns and predicting final height.
Area of Science:
- Pediatrics
- Human Growth and Development
- Biostatistics
Background:
- Linear growth in children is complex, influenced by distinct phases: infancy, childhood, and puberty.
- Individual variations in pubertal timing and growth spurt shape present challenges for standard growth assessment.
Purpose of the Study:
- To assess the ICP (Infancy, Childhood, and Puberty) growth model's ability to describe and evaluate individual growth patterns in healthy children.
- To emphasize the model's utility in accounting for variations in pubertal timing and pubertal growth spurt characteristics.
- To outline the model's application for longitudinal growth evaluation over various periods.
Main Methods:
- Longitudinal analysis of growth data from 157 healthy infants using the ICP growth model.
- Development and application of ICP-based reference standards ('ICP Standard', 'Prepubertal ICP Standard', 'Pubertal ICP Standard').
- Identification of a new final height predictor, HAPO (height adjusted for pubertal onset).
Main Results:
- The ICP model effectively describes individual growth trajectories, accommodating variations in pubertal development.
- ICP Standards offer advantages over cross-sectional standards for evaluating prepubertal and pubertal growth.
- A novel predictor, HAPO, based on pubertal onset age and size, was identified for final height prediction.
Conclusions:
- The ICP growth model provides a robust framework for analyzing and evaluating individual child growth, particularly during puberty.
- ICP Standards facilitate personalized growth assessment, independent of pubertal timing.
- The HAPO predictor offers a new method for estimating final height based on early pubertal characteristics.
Abstract:
The 'ICP growth model' (ICP = Infancy, Childhood and Puberty components) represents linear growth from 3 years of age to maturity by a combination of a slowly decelerating childhood component together with a sigmoid puberty component, the latter acting only during adolescence. Linear growth is analysed for 157 longitudinally followed healthy infants using this model. The main aim is to assess the ability of the ICP model to describe and evaluate individual growth patterns in healthy children with particular emphasis on the considerable individual variation in the timing of puberty and the shape of the pubertal growth spurt. The use of the model to evaluate growth longitudinally over both short and long periods is also outlined. Reference values based on the ICP approach, the ICP Standard, seem to have a number of advantages in comparison with cross-sectional standards. In the 'Prepubertal ICP Standard', the contribution of the puberty component is omitted. The standard can be applied on an individual basis to evaluate prepubertal growth and pubertal onset, independently of the timing of puberty. By using the 'Pubertal ICP Standard' both the difference in pubertal maturation and the negative relationship between the size of the pubertal gain and the timing of puberty are taken into account. The fact that the gain in the puberty component is time-invariant, and can thus be aligned with the timing of puberty for an individual child, forms the basis of this approach. The analyses have also revealed a new predictor for final height, which is termed HAPO (height adjusted for pubertal onset). This predictor is based on age and attained size at onset of puberty--the 'onset' regression line.