Table 2.

The means and standard deviations for CV measurements obtained using the SP-2000P and z-ring CS4, intra-observer repeatability, inter-observer reproducibility (z-ring CS4 only), and comparison between SP-2000P vs. z-ring CS4 (mean differences, limits of agreement, paired t -test, un-paired test, and p-values)

Analysis of CV values	Observer 1		Observer 2
	SP-2000P	z-ring CS4	z-ring CS4
Mean ± SD*	27.12 ± 2.51	27.10 ± 2.41	27.17 ± 2.25
Intra-observer repeatability (p-value)	0.75	0.34	0.98
	Mean difference ± SD*	Limits of agreement	p-value
Inter-observer reproducibility with z-ring CS4**	-0.20 ± 1.20	+3.80, -4.20	0.30
Comparison between SP-2000P vs. z-ring CS4†	0.20 ± 1.45	+3.00, -2.70	0.79

*Standard deviation.

**Paired test.

†Un-paired test.