. Author manuscript; available in PMC: 2012 Sep 1.

Published in final edited form as: J Interv Card Electrophysiol. 2011 Mar 22;31(3):197–206. doi: 10.1007/s10840-011-9560-6

Table 5.

Inter-observer and intra-observer variability

LA functions	Adjusted R²^a	P intercept	P slope	Bias^b	SD of bias	p value for bias
Inter-observer variability
EF (%)	0.83	0.69	<0.001	0.00	0.08	0.98
GS (%)	0.83	0.54	<0.001	–2.49	8.4	0.20
PS-SR (s^–1)	0.83	0.2	<0.001	–0.001	0.2	0.20
ES-SR (s^–1)	0.94	0.78	<0.001	–0.14	0.2	0.30
Intra-observer variability
EF (%)	0.88	0.07	<0.001	0.02	0.07	0.27
GS (%)	0.80	0.83	<0.001	0.70	12.6	0.80
PS-SR (s^–1)	0.82	0.14	<0.001	0.02	0.45	0.80
ES-SR (s^–1)	0.85	0.74	<0.001	0.10	0.47	0.39

LA left atrium, EF emptying fraction, ES-SR end-systolic strain rate, GS global strain, LA left atrium, PS-SR peak systolic strain rate, SD standard deviation

R² values obtained by linear regression from apical four-chamber projection

Bias in this context was the mean difference of data between the first and second observers obtained from Bland–Altman plots