Table 3.

Means and Standard Errors (SEs) for Nitric Oxide (NO) Concentration Change Rate (ppb/d) in Matched Samples Stored at −14 °C and 6 °C

	Storage at −14 °C		Storage at 6 °C
Source	Mean	SE	Mean	SE
Subject’s eNO
13 ppb	0.12	0.12	0.05	0.01
16 ppb	−0.08	0.01	−0.02	0.11
28 ppb	−0.62	0.09	−0.11	0.18
Zero air (initial estimate: 2 ppb NO)	0.38	0.01	0.56	0.02
Ambient air (initial estimate: 160 ppb NO)	−25.58	0.02	−16.99	0.11

Note: eNO = exhaled NO.