Storage conditions for stability of offline measurement of fractional exhaled nitric oxide after collection for epidemiologic research
1 Department of Public Health, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501, Japan
2 Center for Environmental Information Science, 8-19 Yonban-cho, Chiyoda-ku, Tokyo, 102-0081, Japan
BMC Pulmonary Medicine 2012, 12:68 doi:10.1186/1471-2466-12-68Published: 2 November 2012
Additional file 1:
In order to determine whether the different rates of change in NO concentration in the bags stored at 4°C related to smoking category are explained by the differences in initial concentration, the subjects were limited to non-smokers and ex-smokers whose initial FeNO levels were similar to those among current smokers (< 30ppb). In this case, FeNO levels among non-smokers (n = 14) in the bags stored at 4°C were 98.4% ± 5.3% and 113.8% ± 9.1% relative to the baseline values at 9 and 168 hours, respectively, and the values among ex-smokers (n = 4) were 97.0% ± 2.0% and 105.1% ± 7.4%, respectively. These values were smaller than those among current smokers (n = 6). However, the differences were not significant, because of the small number of subjects.
Format: DOC Size: 98KB Download file
This file can be viewed with: Microsoft Word Viewer