Effects of bell versus diaphragm on indirect blood pressure measurement.

The purpose of this study was to determine the effects of using the bell versus the diaphragm of the stethoscope on indirect blood pressure (BP) measurement. The design was experimental. Data were collected from 56 subjects randomly selected from 255 young women. Systolic (S1), fourth phase diastolic (D4), and fifth phase diastolic (D5) values were the dependent variables. Three research hypotheses were tested. Data were analyzed by using a one-tailed t test for dependent means. Hypotheses 1 and 2 predicted that use of the bell would result in higher S1 and D4 readings, respectively, than use of the diaphragm. Hypothesis 1 was supported whereas hypothesis 2 was not. Hypothesis 3, which stated that using the bell would produce a lower D5 reading than using the diaphragm, was supported. Implications of these findings as well as suggestions for future research are discussed.