Table 6. Effect of normalization strategy on statistical parameters calculated for Nppb and Vcam1 expression using single reference genes.

		Tpt1	Hprt	Rpl13a	Ppia	Tbp	Eef1a1	B2m	Actb	Polr2a	Gapdh
Nppb	p-value	<0.001	0.023	0.005	0.023	0.123	0.280	0.631	0.436	0.912	0.005
	power	0.998	0.715	0.933	0.647	0.153	0.231	0.078	0.255	0.107	0.488
	n	5	13	7	14	82	48	296	42	137	20
Vcam1	p-value	<0.001	<0.001	0.001	0.029	0.004	0.631	0.579	0.105	0.796	0.001
	power	0.998	1	0.992	0.619	0.937	0.136	0.059	0.345	0.050	0.997
	n	5	4	6	15	7	96	943	21	>1000	5

Two-tailed Mann-Whitney U test was used for calculating p-values. The statistical power was calculated for a Student's t-test using statistical parameters of log₂ transformed expression data. Sample size (n) is number per group needed to obtain a power of at least 0.8. Nppb: group 2 vs. group 3; Vcam1: group 1 vs. group 3.