Hans van den Heuvel

3 after being acquainted with all devices and procedures. Subjects rested for 5 minutes in seating position before two separate observers started using two calibrated aneroid sphygmanometers (HEINE GAMMA XXL LF) as this is our Unit’s gold standard since mercury sphygmanometers are prohibited for clinical use. 14 The supervisor measured the BP with the automated devices and checked the agreement of the BP values retrieved by the blinded observers. Both iHealth Track and Omron HEM-9210T were assessed sequentially in the same subjects, following this order and with 30-60s rest between readings: Entry measurements: Observer 1, Observer 2, Device, Validation measurements: Observer 1 – Observer 2 – Device - Observer 1 – Observer 2 – Device - Observer 1 – Observer 2 – Device - Observer 1 – Observer 2. The last sevenmeasurements were analysed following the protocol. Analysis Observer – device differences were classified for systolic and diastolic values in three groups; within 5, 10 and 15 mmHg variability. Details of this procedure are published in the protocol (11) . The pass requirements of Part 1 (See Results- Table 2 and 3) state that within these 3 variability groups, of 99 device-observer measurement comparisons, at least two of 73/87/96 boundaries OR all of the 65/81/93 boundaries should be met. The pass requirements of Part 2 (See Results – Table 2 and 3) state that at least 24 of 33 subjects should have two or three absolute differences between observer and device measurements within 5mmHg. Nomore than 3 subjects are allowed to have none of the absolute differences between observer and devicemeasurements within 5mmHg. Differences between observers and devices and 95% limits of agreement were visualized in Bland-Altman plots. VALIDATION STUDY OF TWO BLOOD PRESSURE MONITORS IN PREGNANCY 43