Auscultatory measurement of blood pressure performed by the doctor on duty.

A review is presented of the measurements of blood pressure on admission of 600 patients to the wards in a department of general medicine. Three doctors each examined 200 patients, distributed over two periods with an interval of one year. Large differences were found between the doctors as regards the distribution of the BPs, particularly the diastolic pressures. On the other hand, no differences were observed in the distributions during the two periods as far as the individual doctors were concerned. Great preference was shown for zero as the terminal digit and also for certain BP values. It is concluded that the observer introduces a considerable subjective factor in measuring the BP by auscultation. Correct performance of this simple procedure requires meticulous instruction.