Validation of the Oregon Scientific BPW810 blood pressure monitor according to the European Society of Hypertension Protocol

OBJECTIVE: To determine the accuracy of the BPW810 blood pressure monitor developed by IDT Technology Limited, according to the international protocol of the European Society of Hypertension. DESIGN: The international protocol is divided into two phases: the first phase is performed on 15 selected participants and, if the device passes this phase, 18 more participants are included making a total of 33 participants on whom the final validation is performed. METHOD: According to the European Society of Hypertension requirements, for each of the 33 participants, four blood pressure measurements were taken simultaneously by two trained observers, using mercury sphygmomanometers alternately with three measurements by the test device. The difference between the blood pressure value given by the device and mean of the two observers' readings was calculated for each measurement. The 99 differences were classified into zones (< or =5, < or =10, and < or =15 mmHg). The number of differences in each zone was compared with the number required by the international protocol. Furthermore, an individual analysis was then done to determine for each participant the number of comparisons < or =5 mmHg, which requires that at least 22 of the 33 participants should have two of three comparisons < or =5 mmHg. RESULTS: The BPW810 passed the first phase of the validation process for systolic and diastolic blood pressure. For the second phase, the difference between the device and mean of two observers was -2.2+/-4.8 mmHg for systolic blood pressure and -0.5+/-3.7 mmHg for diastolic blood pressure. In the last phase, 26 participants fell in the zone of two of the three comparisons lying within 5 mmHg and none of the participants fell in the zone of all three of the comparisons over 5 mmHg apart. CONCLUSION: The BPW810 passed all the phases of the international protocol for both systolic and diastolic blood pressure.