Comparison of classic and 4-phase rhinomanometry methods, is there any difference?

Background: There are various different parameters used to measure nasal airway resistance (NAR) in rhinomanometry, which include the classic method at fixed pressure of 150Pa or 75Pa and 4-phase rhinomanometry. This study aims to determine if there is any difference between the measurements of NAR obtained by the classic and 4-phase rhinomanometry methods.

Methodology: In-vitro study with measurements of NAR using both methods when applied across four artificial nose models.

Results: No statistically significant differences were found between NAR values obtained from both methods. Strong, positive correlations were found between NAR measured with both methods, which were statistically significant. Bland-Altman method also showed good agreement between both methods with narrow limits of agreement.

Conclusion: There is high level of conformity between the values of nasal airway resistance measured using both methods.