. Author manuscript; available in PMC: 2023 Apr 1.

Published in final edited form as: J Hypertens. 2022 Aug 23;40(10):2037–2044. doi: 10.1097/HJH.0000000000003228

Table 3. Regression of central aortic SBP on brachial SBP measured via noninvasive cuff and invasive recordings.

	n	β (95% Cl)	P	R^2b (95% Cl)^c	P	RMSE (95% Cl)^c	P
Device 1 - unadjusted models
Estimated aortic SBP ~ cuff SBP	171	0.89 (0.86; 0.92)	<0.001	0.96 (0.95; 0.98)		3.13(2.80; 3.46)
Invasive aortic SBP ~ brachial SBP	171	0.91 (0.86; 0.97)	<0.001	0.85 (0.81; 0.90)		8.04(7.22; 8.86)
Difference ^c				0.11 (0.07; 0.15)	<0.001	–4.91 (–5.74; –4.08)	<0.001
- Adjusted models^a
Estimated aortic SBP ~ cuff SBP	164	0.89 (0.86; 0.92)	<0.001	0.96 (0.95; 0.97)		3.19(2.86; 3.52)
Invasive aortic SBP ~ brachial SBP	164	0.89 (0.83; 0.94)	<0.001	0.88 (0.84; 0.92)		7.09(6.29; 7.90)
Difference ^c				0.08 (0.04; 0.11)	<0.001	–3.90 (–4.70; –3.10)	<0.001
Device 2 - unadjusted models
Estimated aortic SBP ~ cuff SBP	52	1.03 (0.96; 1.09)	<0.001	0.95 (0.92; 0.98)		4.01 (3.28; 4.75)
Invasive aortic SBP ~ brachial SBP	52	0.95 (0.86; 1.05)	<0.001	0.89 (0.85; 0.94)		6.74 (5.80; 7.69)
Difference ^c				0.06 (0.02; 0.09)	≤0.001	–2.73 (–3.81;–1.65)	<0.001
- Adjusted models^a
Estimated aortic SBP I cuff SBP	40	1.05 (0.98; 1.12)	<0.001	0.97 (0.95; 0.99)		3.63(2.79; 4.46)
Invasive aortic SBP I brachial SBP	40	0.95 (0.84; 1.07)	<0.001	0.89 (0.84; 0.95)		7.16(5.74; 8.58)
Difference ^c				0.08 (0.03; 0.13)	0.002	–3.53 (–5.02; –2.04)	<0.001

Sphygmocor Xcel and Uscom BP+ were defined as device 1 and device 2. respectively. Data are unstandardized beta (95% confident interval).

Models are adjusted for age. sex, height, and invasive aortic heart rate.

Adjusted R2.

Adjusted R2 (95% Cl) and RMSE (95% Cl) differences between noninvasive and invasive models calculated by bootstrapping with 2000 replications Cl. confidence interval, RMSE. root mean square error: SBP systolic blood pressure.