The studies for this report were made on men who applied for examination for the American Army Aviation Service. It may readily be seen that a long period of study could not be given to each applicant without causing unwarranted delay to the applicant and also to the other examiners. A Tycos instrument, daily tested with a mercurial sphygmomanometer, was used for all blood pressure estimations. All readings were made by one examiner in order to reduce the personal factor to as small an error as possible.
Readings were made with applicants in (1) the recumbent position; (2) standing, before exercise, and (3) standing, after measured exercise. The readings, in the first position, were made after the nervous excitement had become controlled as much as possible. This factor was commonly very prominent and often difficult to control, sometimes requiring the subject to return for a later reading. For the exercise
SMITH B. BLOOD PRESSURE STUDIES OF FIVE HUNDRED MEN. JAMA. 1918;71(3):171–174. doi:10.1001/jama.1918.02600290013005