Auxology: an update.

Area of Science:

• Pediatric endocrinology and growth monitoring
• Human growth and development analysis
• Biostatistics in clinical research

Background:

• Accurate human growth documentation is crucial for assessing child development.
• Individual growth is typically evaluated against reference populations using percentiles or standard deviation scores (SDS).
• Variations in SDS (crossings) are physiological and indicate changes in developmental tempo.

Purpose of the Study:

• To re-evaluate established methods for assessing human growth and height changes.
• To foster consensus on the appropriate clinical evaluation of height and its velocity.
• To differentiate and quantify the contributions of tempo and amplitude to height variance.

Main Methods:

• Utilizing functional data analysis (FDA) and principal component analysis (PCA).
• Analyzing individual growth measurements plotted as percentiles or SDS.
• Quantifying tempo and amplitude as primary sources of height variance.

Main Results:

• Approximately two-thirds of children and adolescents exhibit >1 SD height crossing between childhood and adulthood.
• Pubertal growth shows characteristic SDS peak patterns (upward for faster tempo, downward for slower tempo).
• Growth tempo accounts for nearly half of the variation in height during puberty.

Conclusions:

• Growth tempo and amplitude are statistically separable and quantifiable components of height variance.
• Understanding SDS dynamics, particularly during puberty, is essential for accurate growth assessment.
• This review advocates for refined methods to evaluate height velocity and overall growth patterns.