Repeatability of successive measurements with a portable nitric oxide analyser in patients with suggested or diagnosed asthma

Abstract

The objective of our study was to determine the repeatability of successive measurements of exhaled nitric oxide (NO) with a portable device (NIOX MINO). We assembled a sample of 332 pairs of repeated NO measurements acquired in the same session. The mean of the two successive measurements varied from 4.0 to 279.5 parts per billion (ppb). The mean coefficient of repeatability (CoR) of the entire study sample was 2.4 ppb. The difference between paired measurements increased slightly with increasing fractional exhaled nitric oxide (FENO); for the mean FENO of 24.0 ppb the calculated CoR was 2.2 and for the FENO of 54 ppb it was 3.2 ppb. The difference between paired observations for FENO values <50 ppb was significantly lower than that for values >50 ppb (p<0.001). The demonstrated repeatability of successive measurements with the device supports the view that, when the exhalation manoeuvre is technically valid and FENO is within normal limits, repeated determinations of FENO are generally not necessary for screening. In other cases, the mean value of two successive measurements would represent a more reliable measurement result.

Validation of a New Portable Exhaled Nitric Oxide Analyzer, NIOX VERO®: Randomized Studies in Asthma

“…FeNO measurements using NIOX VERO Ò were reproducible, consistent and well within the technical specifications of the device. Our findings correlate with previous observations with NIOX MINO Ò ; other studies in adults and children have reported excellent reproducibility when using this device [11,21,22,25,29,30,32,33]. However, poor [19].…”

Increased Exhaled Nitric Oxide Levels After Exercise in Patients With Chronic Systolic Heart Failure With Pulmonary Venous Hypertension

“…In 50% (17 out of 34) of subjects, resting eNO was measured. The mean coefficient of variation of the measurement was 2.4 ppb and consistent with published report 11 .…”

Childhood Asthma Control Test and airway inflammation evaluation in asthmatic children

“…It has been validated with the existing technology based on chemiluminescence with accuracy of ±5 ppb compared to NIOX (Aerocrine AB), showing an average disagreement of 0.5 ppb with a mean SD of 3.8 ppb, and a high linearity and accuracy when compared with reference gases (18, 19). On the basis of the data provided by the manufacturer, which included sensor stability within 5 ppb or 15% throughout its lifetime, the device was 510(k) cleared (K072816) by FED, it has been demonstrated to be repeatable (20) applicable in research and clinical practice (21) and it has been used in a number of recent cross‐sectional and longitudinal clinical studies (22–26).…”