These figures result from the National Child Measurement Programme (NCMP), which assesses how children are growing. Children are measured in their reception year (aged 4-5 years) and again in year 6 (aged 10-11 years). Healthcare professionals record their height and weight, as well as age and gender, to determine their body mass index, or BMI.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/are-bmi-charts-useful-for-children