title: Assessment of exhaled nitric oxide by a new hand-held device.
abstract: BACKGROUND
  Fractional exhaled nitric oxide (FENO) has been implicated as a pulmonary biomarker. The aim of this study was to compare the performance of a new hand-held device to a standard chemiluminescence analyzer and to another portable device.
  
  
  METHODS
  FENO levels measured by NObreath (Bedfont) were compared to those of (1) a chemiluminescence detector (Logan, Logan Research) and (2) the electrochemical portable NIOX MINO (Aerocrine) in 18 healthy volunteers on three consecutive occasions: in the morning, 1 h and 24 h later.
  
  
  RESULTS
  Comparing FENO levels obtained by NObreath to those by Logan values were similar and a very close linear relationship was found between the two devices (r = 0.923, p < 0.001). The mean inter-device difference in FENO level was -3.45 ppb and the limits of agreement (Bland-Altman test) were -10.98 and 4.08 ppb. In the second series FENO levels obtained by NObreath were found to be slightly higher compared to those of NIOX MINO, but still showed a close correlation (r = 0.681, p < 0.001). The mean inter-device difference in FENO level was 4.36 ppb and the limits of agreement were -7.38 and 16.1 ppb. Analyzing the repeated FENO measurements, the mean coefficient of variation using NObreath tended to be lower than that of NIOX MINO (16.9 vs. 24.7%, p = 0.059), while it was similar as the value obtained with Logan (11.8 vs. 9.0%, p = 0.342).
  
  
  CONCLUSIONS
  FENO values measured with NObreath are reproducible and in good agreement with those obtained by NIOX MINO and Logan indicating that NObreath is suitable for use in clinical practice.
authors.affiliation: Department of Pathophysiology, National Koranyi Institute for TB and Pulmonology, Budapest, Hungary. antusb@hotmail.com
authors.forename: Balazs
authors.initials: B
authors.lastname: Antus
authors.forename: Ildiko
authors.initials: I
authors.lastname: Horvath
authors.forename: Imre
authors.initials: I
authors.lastname: Barta
mesh_terms: D015415:Biomarkers / Q000032:analysis; D001944:Breath Tests / Q000295:instrumentation*; D034201:Computers, Handheld; D004867:Equipment Design; D045853:Exhalation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide