Related Experiment Video
Updated: Aug 2, 2026

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults
Published on: February 9, 2022
Normal values and predictive equations for aerodynamic function in British Caucasian subjects
1Speech Therapy Department, Bristol Royal Infirmary, UK.
Abstract:
Many useful objective measurements of air volume and flow may be made with a high degree of validity and reliability using present-day respirometers within a speech clinic. We have studied measures of aerodynamic function in 76 British Caucasian subjects and derived reference equations for mean flow rate (MFR), phonation quotient (PQ), vocal velocity index (VVI), phonation time and the phonation volume/vital capacity ratio. Measures from resting breathing patterns have also been investigated. Age was found to be an important determinant in the reference equations. MFR, PQ and VVI were all greater than previously reported. The equations derived in this study should provide a more appropriate assessment of aerodynamic function than the previously reported normal ranges.
Related Concept Videos
Respiratory Volumes and Capacities
Dimensionless Groups in Fluid Mechanics
Correlation of Experimental Data
For example, a spherical particle moving through a viscous fluid experiences drag. Dimensional analysis shows that the drag force depends on the particle's diameter, velocity, and...
Major Losses in Pipes
Fluid flow can be classified as laminar or turbulent, primarily based on the Reynolds number. This dimensionless number reflects the relative influence of inertial to viscous...
Lift
Average Value of a Function

