Comparison of the Omron RS6 wrist blood pressure monitor with the positioning sensor on or off with a standard mercury sphygmomanometer

OBJECTIVE: The aim of the present study was to evaluate the measurement accuracy of Omron RS6 with positioning sensor on (PSON) in comparison with Omron RS6 with positioning sensor off (PSOFF). The Omron RS6 has passed the 2010 version of the European Society of Hypertension International Protocol previously. METHODS: A total of 85 adult participants (39 male and 46 female) were recruited. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were sequentially measured using a standard mercury reference sphygmomanometer (ERKA 3000; two observers) and Omron RS6 with PSON or PSOFF. RESULTS: A total of 85 participants (39 men, 46 women) were included in this study, with a mean age of 53.5±16.4 years. SBP at entry was 133.0±19.9 mmHg and DBP was 81.3±11.8 mmHg. The two observers for SBP and DBP measurements were in good agreement, with agreements of -0.2±1.5 mmHg for SBP and -0.2±1.5 mmHg for DBP, respectively. The mean difference between PSON readings and readings from the standard device was -2.6±6.1 mmHg for SBP and -1.4±4.8 mmHg for DBP. The differences in PSOFF readings were -4.5±6.9 and -3.2±5.4 mm Hg, respectively (P<0.01; PSON vs. PSOFF). A higher proportion of patients had a small deviation (≤5 mmHg) from the reference device when the positioning sensor was on (65 vs. 54% for SBP and 76 vs. 65% for DBP readings). Using the positioning sensor, the variation in wrist height compared with PSOFF decreased. CONCLUSION: The Omron RS6 position sensor is an important function for a wrist device that improves measurement accuracy by decreasing variations in wrist height.