Table 5.

Comparison of Progesterone Levels at National Hormone Laboratory (PPVI) with Outside Laboratories

Range Testeda	$\overline{\text{X}}$ NHL/PPVI	$\overline{\text{X}}$ Outside Labb	p Value
0.1–1.0b (n = 15)	0.69	1.03	<0.025c
1.1–3.0 (n = 17)	2.25 [1.98–2.52]d	2.33 [1.46–3.20]d	NSc
3.1–7.5 (n = 38)	5.25	6.51	<0.005e

^a From Pope Paul VI Institute (PPVI)/ National Hormone Laboratory (NHL) data. NS: Not statistically significant.

^b Comparison levels from multiple different laboratories.

^c Paired t-tests.

^d95.0 percent confidence limits.

^e Wilcoxon Signed-Rank test for difference in medians.