Table 4.

Comparison of System Usability Scores by Device

				95% CONFIDENCE INTERVAL
DEVICE 1, DEVICE 2	MEAN DIFFERENCE (DEVICE 1 AND 2)	STANDARD ERROR	P VALUE	LOWER BOUND	UPPER BOUND
Watch
BP cuff	0.24	0.37	0.534	−0.53	0.99
Weight scale	−0.97	0.25	<0.001a	−1.48	−0.47
Tablet	0.53	0.49	0.291	−0.48	1.54
BP cuff
Watch	−0.24	0.37	0.534	−0.99	0.53
Weight scale	−1.21	0.35	0.002a	−1.92	−0.49
Tablet	0.30	0.61	0.634	−0.95	1.54
Weight scale
Watch	0.97	0.25	<0.001a	0.47	1.48
BP cuff	1.21	0.35	0.002a	0.49	1.92
Tablet	1.50	0.48	0.004a	0.52	2.48
Tablet
Watch	−0.53	0.49	0.291	−1.54	0.48
BP cuff	−0.29	0.61	0.634	−1.54	0.95
Weight scale	−1.50	0.48	0.004a	−2.48	−0.52

^ap < 0.02 indicates a significant difference.

BP, blood pressure.