Growth Percentiles: What Are They and How to Interpret Them?
Child development is a journey of physical, cognitive and emotional growth and growth percentiles are a valid tool for assessing a child's growth and development.
In this article, you will be able to discover the meaning and application of the growth percentiles used by Pediatricians.
What are growth percentiles?
Centile charts are a measurement tool used to evaluate a child's growth , considering weight and height, in relation to the parameters established by the World Health Organization. These charts are based on a representative sample of 1000 children of the same age and sex. The sample is divided into 100 subgroups, each consisting of 10 children, and each of these subgroups is called a centile.
Each centile represents 1% of the child population of the age taken into consideration. For example, in the first centile are placed the children of the smallest height and weight, while in the hundredth centile are found the most robust and developed.
The distribution of most of the child population is concentrated between the 25th and 75th percentile , indicating that the majority of children have dimensions considered normal compared to the reference sample. This tool allows health professionals to monitor and evaluate the growth of children in the context of a reference population, facilitating the detection of any significant deviations that may require further medical evaluation.
New WHO growth curves
On April 27, 2006, the World Health Organization (WHO) presented its new growth curves , representing an important step forward after a journey that began in 1994. In fact, in that year, the inadequacy of the 1977 National Center for Health Statistics (NCHS) curves, based on a sample of US children primarily fed formula, was recognized.
The new curves took into consideration samples of children who were subjected to severe dietary standards:
- Exclusive or predominant breastfeeding for at least 4 months.
- Continued breastfeeding for up to 12 months.
- Introduction of nutritionally adequate complementary foods between 4 and 6 months.
However, these curves differ in several aspects from the previous ones and from those recommended in various countries, including Italy.
Differences from Previous Curves
Growth curves
To adequately assess the growth of the child, growth percentile tables are used, whose curves provide an indication of the growth trend in terms of height and weight . Each child follows his or her own developmental rhythm and it is up to the pediatrician to interpret the data expressed through the percentiles.
Height and weight are the main parameters that the pediatrician uses to monitor the child's progress, considering age and sex. Below you can also find the links to download the new curves from the ISS (Istituto Superiore di Sanità) website:
- Weight-for-age growth percentile table: https://www.who.int/tools/child-growth-standards/standards/weight-for-age
- Height-for-age growth percentile table: https://www.who.int/tools/child-growth-standards/standards/length-height-for-age
- Growth percentile table for head circumference: https://www.who.int/tools/child-growth-standards/standards/head-circumference-for-age