Objective: A prospective study in a healthy French population to evaluate the normal range of PNIF.
Material and methods: In total, 234 subjects separated into 2 groups (group 1: patients with VAS >or= 8, n = 151 and group 2: patients with VAS < 8, n = 83) have been prospectively enrolled in this study from September 2003 to April 2004. For all participants, nasal obstruction was evaluated through a VAS and two PNIF measurements.
Results: The mean PNIF measurements in group 1 and group 2 were 87.5 L/min and 84.7 L/min, respectively with a significant difference between male and female in both groups (p < 0.0001). The reproducibility in group 1 and group 2 was 5.1 L/min and 4.4 L/min respectively. A slight tendency to a reduction due to the age was observed except for patients over 60.
Conclusion: This study confirms that the technique of PNIF measurement is reliable and simple. The normal range of PNIF in a healthy French population has been determined although our results show lower values than previous published reports from other countries. However, it remains an attractive method for the follow-up and survey of patients complaining of nasal obstruction.