Table 2.

Comparisons of WatchBP Office Central with the high-fidelity intra-arterial reference standard (Study 1).

	n	Comparisons	WatchBP	Reference	Difference	95% Confidence Interval
cSBP-WBP vs cSBP-IA	11	25	105.1 ± 10.7	79.0 ± 12.5*	26.1 ± 7.4	23.1–29.1
bSBP-WBP vs cSBP-IA	14	29	92.4 ± 10.6	79.9 ± 11.1*	12.5 ± 6.0	10.2–14.8
bSBP-WBP vs bSBP-Tx	11	11	90.3 ± 12.0	78.7 ± 11.7*	11.6 ± 5.8	7.7–15.6
bDBP-WBP vs cDBP-IA	14	29	49.1 ± 8.1	49.0 ± 10.0	0.1 ± 5.6	−2.1 to 2.2

Data presented as mean ± standard deviation. Pressures are in mmHg. Comparisons refer to the number of individual recordings being compared. There were three fewer participants for the cSBP-WBP comparison, as despite the test device providing an error for cSBP, it reported valid brachial pressures. Adequate tonometry waveforms could not be obtained in three participants.

bDBP/cDBP brachial/central diastolic blood pressure, bSBP/cSBP brachial/central systolic blood pressure, IA intra-arterial (ascending aorta), Tx obtained via the brachial tonometry waveform calibrated to intra-arterial (aortic) mean and diastolic pressures, WBP Watch BP (test device).

*p < 0.001 comparing WatchBP vs the reference method.