The Range and Distribution of Blood Pressures in Normal Children

The usefulness of blood pressure determination as means of diagnosis has long suffered from the lack of suitable standards which would define accurately the limits of normal tension and of pathologic hypotension or hypertension.We are abundantly supplied with averages, but averages have, at best, an academic value unless they are supplemented by standards of normal deviation from the average.Particularly in pediatrics, the lack of such standards of deviation has resulted in the neglect of sphygmomanometry as having too little prac- tical value.It has seemed to us that much useful information regarding the cardiovascular functions and disturbances of childhood might be obtainable once the desired normal standards were established, and it was in an effort provisionally to formulate such standards that the present study was undertaken.Not only blood pressure statistics but nearly all medical statistics have been organized in such a way as to give averages only.In some instances, authors have attempted to furnish maximum and minimum values also, but, realizing the unreliability of absolute maximum and minimum findings, they have determined the average maximum and average minimum values, a method which may justly be criticized.In general, the range has been disregarded, not because it is not important ' to know but because it is very difficult satisfactorily to define.GENERAL PRINCIPLES * It has of course been realized that individual measurements, as of blood pressure, always deviate to some extent from the average and