It is needed to confirm the presence of hypertension on the basis of three blood pressure measurements at separate clinical visits.

Normative BP percentiles are based on data on gender, age, height, and blood pressure measurements from the National Health and Nutrition Examination Survey and other population-based studies.

A study published in the journal Pediatrics in 2013 noted that the initial BP measurement was normal (below the 90th percentile), pre–hypertensive (systolic or diastolic BP between the 90th or 95th percentile) and hypertensive (systolic or diastolic BP ≥95th percentile) in 82%, 13%, and 5% of children.

At follow–up, subsequent hypertensive measurements were noted in just 4% of the 10,848 children who had shown initial hypertensive values. The overall prevalence of hypertension in the cohort was 0.3%.