Phonatory aerodynamic system ; Voicing efficiency ; Repeated measures ; Subglottal pressure ; Mean airflow rate
Abstract
Objectives: The purpose of the present study was to determine whether voicing efficiency measures derived from the Phonatory Aerodynamic System differ according to repeated trials and the presence of voice disorders upon controlling for severity. In addition, the diagnostic ability of the first and averaged measures were compared. Methods: A total of 160 participants (80 patients and 80 controls; 23 males and 57 females for each group) participated in the study. Each participant was asked to perform the voicing efficiency protocol three times. Selected aerodynamic parameters including mean sound pressure level (PHODB), mean pitch (MEAP), mean peak air pressure (MPAP), mean airflow during voicing (MFPHO) were measured. A two-way repeated measures of ANCOVA upon controlling for severity and ROC curve analysis were performed. Results: Results indicated that there was no difference in MPAP and MFPHO among repeated trials upon controlling for severity, although a significant difference was found in PHODB (trial 1