Comparison of Labial and Mechanical Interruption for Measurement of Aerodynamic Parameters

• Published in: Journal of voice Vol. 25; no. 3; pp. 337 - 341
• Main Authors: Chapin, William J., Hoffman, Matthew R., Rieves, Adam L., Jiang, Jack J.
• Format: Journal Article
• Language: English
• Published: United States Mosby, Inc 01.05.2011; Elsevier Science Ltd
• Subjects: Air Flow; Catheterization; Comparative Studies; Flowmeters; Humans; Labial interruption; Laryngeal airflow; Laryngeal resistance; Laryngology; Larynx - physiology; Measurement; Mechanical interruption; Otolaryngology; Otolaryngology - instrumentation; Otolaryngology - methods; Phonation; Pressure; Reproducibility of Results; Respiration; Rheology; Speech Acoustics; Speech Pathology; Subglottal Pressure; Time Factors; Voice; Voice Disorders; Subglottal pressure; Laryngeal resistance; Labial interruption; Laryngeal airflow; Mechanical interruption
• ISSN: 0892-1997; 1873-4588; 1873-4588; 1557-8658
• DOI: 10.1016/j.jvoice.2010.01.004

To directly compare the mechanical and labial interruption techniques of measuring subglottal pressure (P s), mean flow rate (MFR), and laryngeal resistance (R L). Thirty-four subjects performed 10 trials with both mechanical and labial interruption. P s and MFR were recorded, whereas R L was calculated by dividing P s by MFR. Coefficients of variation were calculated to compare intrasubject precision. A subset of 10 subjects performed the tasks twice with 30 minutes between sessions. Bland-Altman plots were used to determine intrasubject repeatability for each of the methods. Mechanical interruption produced coefficients of variation for P s, MFR, and R L of 0.0995, 0.127, and 0.129, respectively. Labial interruption produced coefficients of variation of 0.102, 0.147, and 0.169, respectively. P values were 0.824 for P s, 0.159 for MFR, and 0.043 for R L. The Bland-Altman plots revealed comparable repeatability between the two methods. The 95% confidence intervals of the Bland-Altman plots for mechanical interruption were (−0.050, 0.072), (−0.543, 1.832), and (−2.498, 10.528) for MFR, P s, and R L. Confidence intervals for labial interruption were (−0.018, 0.031), (0.057, 2.442), and (−3.267, 10.595) for MFR, P s, and R L. Mechanical interruption produced higher precision when measuring R L because of more reliable airflow measurements. Mechanical and labial interruption showed comparable repeatability. Further research into using mechanical interruption clinically is warranted.