Table 3.

Comparing single-lead ECGs with leads I and II of 12-lead ECGs in paired samples

			Paired differences					T	Sig. (2-tailed)
			Mean diff.	SD mean	SE mean	95% CI of diff.
						Lower	Upper
Heart rate (/min)	Single-lead vs	Lead II	0.79	5.36	0.48	−0.16	1.74	1.65	0.10
QRS (ms)	Single-lead vs	Lead I	1.55	11.35	1.03	−0.50	3.59	1.50	0.14
		Lead II	1.13	11.36	1.03	−0.91	3.17	1.10	0.27
QT (ms)	Single-lead vs	Lead I	0.13	19.13	1.74	−3.57	3.31	0.07	0.94
		Lead II	9.39	20.99	1.90	−13.16	−5.63	4.94	<0.001
QTcB (ms)	Single-lead vs	Lead I	1.29	21.32	1.94	−2.55	5.12	0.66	0.51
		Lead II	7.78	21.89	1.98	−11.70	−3.85	3.92	<0.001

diff., difference; QTcB, corrected QT time by Bazett’s formula; Sig. (2-tailed), two-tailed significance of t-value; T, t-value.;