Table 3.

The concentrations of 21 prostate metabolites for seven sample pairs with relative differences of epithelial volume percentages less than 20% within each pair. Metabolite concentrations (means and standard deviations) obtained in 2002 are compared with those measured in 2005 together with their respective p-values (without Bonferroni corrections) of paired t-tests. Also included in this table are the power calculations to determine the levels of Type II errors for each measured metabolite. These calculations are based on the standard deviations measured with the seven-pairs of samples, using two-sided evaluation of a 5% significant level, and at an 80% power level to determine the minimal detectable differences in metabolite concentrations for each metabolites and presented in the table as the percentage of the 2002 values. These 21 metabolites included all the reported metabolites in Ref. (Wu et al. 2003).

	2005		2002		Paired t-Test	Detectable Diff (%)
	Mean	SD	Mean	SD
Lac(4.10–4.14)a	14.29	3.98	12.87	6.68	0.38	38.9
MI(4.05)	10.30	2.77	12.57	5.39	0.31	54.4
3.60–3.63b	16.98	6.78	20.17	13.57	0.56	78.8
3.34	5.18	2.08	5.49	1.95	0.82	61.9
3.29	1.11	0.63	2.53	2.13	0.13	108
3.27	8.79	2.38	11.17	5.60	0.30	62.8
3.25–3.26	12.22	3.32	13.95	5.85	0.26	33.8
Pch(3.22)	1.05	0.28	1.44	1.05	0.38	95.1
Chol(3.20)	1.53	0.22	1.70	0.91	0.64	67.1
Spm(3.05–3.14)	1.75	2.69	2.21	1.72	0.52	103
Cr(3.03)	2.66	0.92	5.19	3.69	0.08	76.3
Cit(2.70–2.73)	4.87	1.86	3.44	1.66	0.19	94.4
2.31–2.37	5.60	2.13	10.17	3.32	0.06	48.1
2.01–2.14	29.67	14.92	42.51	6.99	0.13	47.3
Acet(1.92)	1.36	3.02	1.19	2.54	0.44	58.8
1.68–1.78	10.89	7.11	10.98	7.34	0.98	124
Ala(1.47–1.49)	1.00	0.42	1.52	1.13	0.18	75.7
Lac(1.32–1.34)	17.45	4.18	20.53	9.80	0.37	51.6
1.19–1.20	2.70	2.30	2.13	2.67	0.35	91.1
1.04–1.05	0.51	0.32	1.59	2.21	0.25	183
Lipid(0.90)c	22.87	5.11	14.65	6.55	0.03	84.6