It has been increasingly accepted that there is a long-term correlation between blood pressure in childhood and adulthood. Hence, it is significant to monitor childhood blood pressure. The 90th and 95th percentiles of blood pressure for specific age, sex and height groups were presented in the Update for the 1987 Task Force Report on Blood Pressure control in children, arid widely distributed by the National High Blood Pressure Education Program. There has been a recent update to the Task Force Report (Pediatrics, 2004) which used more current height percentiles based on CDC (2000) growth charts and extends the percentiles provided to include the 50th, 90th, 95th, and 99th percentiles. However, the percentiles are based on all children including both obese and non-obese children. Thus, in the present application, we propose to (a) broaden the percentiles presented so as to display the full range of blood pressure percentiles from the first to the 99th percentile (b) evaluate the percentiles for children of normal body weight so as to disentangle the relationship between hypertension and obesity (c) provide a algorithm using Microsoft Access for computation of a blood pressure percentile or Z-score in a user-friendly format (d) provide percentiles for both K4 and K5 diastolic blood pressure (the Task Force Report only includes percentiles for K5 DBF) and (e) compare childhood blood pressure percentiles by ethnic group. A 2nd aim of this application is to develop screening rules for detecting high blood pressure in children. Given the existence of new Task Force Norms that quantify percentile values of blood pressure in children by age, sex and height, an significant issue is how to use these norms to effectively screen children for high blood pressure, where high blood pressure is defined as having an average blood pressure > 95' percentile for a given age, sex and height based on task force percentiles over a large number of visits. The goal is to develop efficient screening rules that maximize accuracy with the fewest screening visits necessary per child. The screening rules will be assessed in simulation studies and tested in a sample of 16,000 Houston school children who were screened for high blood pressure by Dr. Ronald Portman. The general theme linking the major aims of the application is a comprehensive assessment hypertension in children both with respect to the definition of high blood pressure as well as the development of screening rules to efficiently identify children who satisfy this definition. [unreadable] [unreadable]