Correlation of nasal symptoms with objective findings and surgical outcome measurement

Thesis submitted for the degree of Master of Surgery, University of London, 1993.
Published (excluding Chapter 9) 1996.
Recompiled HTML format June 2007
© 1993 – 2014 JW Fairley

Mr James W Fairley BSc MBBS FRCS MS
Consultant ENT Surgeon

Chapter 2
Correlation of subjective sensation of nasal patency with nasal inspiratory peak flow rate in healthy volunteers*

Thesis Contents

Summary

To determine the relationship between subjective sensation of nasal patency and objective measurement of nasal inspiratory peak flow rate (NIPF), I carried out a prospective longitudinal study on healthy volunteers.

Five healthy medical practitioners, one woman and four men, aged 24 to 34 years, made daily subjective estimations of their sensation of nasal patency on a 10 cm visual analogue scale. This was followed immediately by measurements of nasal inspiratory peak flow rate using a Youlten meter, repeated on at least 25 days per subject. Correlation coefficient and regression lines for subjective nasal patency on nasal inspiratory peak flow rate were calculated. 169 sets of observations were made, range 25-44 per subject.

Each subject showed strong evidence (p <0.01) of positive correlation between subjective nasal patency score and nasal inspiratory peak flow rate. There was strong evidence (p <0.001) that different regression lines are needed for different subjects, but no evidence that the lines are not parallel.

Subjective sensation of nasal patency is strongly correlated with objective nasal patency, as measured by peak inspiratory flow rate. This relationship varies between individuals. The coefficient of variation of the measurement itself was 8%, compared with an overall coefficient of variation of 25%, ratio over 3:1. This indicates that the measurement, although rather imprecise, is sufficiently sensitive to detect effects that are large enough to be of clinical relevance.

Measurement of nasal inspiratory peak flow rate may be a valuable objective test of nasal patency, and is quick and simple to perform.

* Major part of this work previously published: Fairley JW, Durham LH, Ell SR. (1993) Correlation of subjective sensation of nasal patency with nasal inspiratory peak flow rate Clinical Otolaryngology 18; 19-22