The diagnosis of hypertension should be confirmed based on 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.

In a study, 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, respectively.

At follow-up, subsequent hypertensive levels were observed in only 4% of the 10,848 children with initial hypertensive values. The overall prevalence of hypertension in the cohort was 0.3%.