Related Experiment Video
Updated: Mar 12, 2026

Foreign Accent and Forensic Speaker Identification in Voice Lineups: The Influence of Acoustic Features Based on Prosody
Published on: September 27, 2024
Influence of Glottal Fry on Acoustic Voice Assessment: A Preliminary Study
Laura W Plexico1, Mary J Sandage1
1Department of Communication Disorders, Auburn University, Auburn, Alabama.
Purpose:
This preliminary study examined the influence of glottal fry on measurement of speaking fundamental frequency (SF0) and whether sex differences influence the impact glottal fry has on SF0 and cepstral peak prominence (CPP). It was hypothesized that SF0 and CPP would decrease as percent glottal fry in the sample increased, with larger changes observed in the female voice.
Methods:
Twenty-six participants (13 men, 13 women) completed the study. Participants were recorded reading the Rainbow Passage. SF0 and CPP were determined from the original sample. Percent glottal fry SF0 was determined and semitone change was recalculated after removal of glottal fry from the sample. Regression analysis was used to determine the impact of glottal fry and sex on semitone change and CPP differences in SF0.
Results:
Significant differences were found for both sex and percent glottal fry on semitone change in SF0. A significant relationship was not found between CPP and semitone change when sex was accounted for.
Conclusions:
Findings from this study indicate that the measurement of SF0 for women will decline as percent of glottal fry increases. These findings have clinical implications for interpretation of SF0 measurement and evidence-based outcomes for voice therapy.
Related Concept Videos
Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
Larynx
Anatomy of the Larynx
The larynx consists of various components, including cartilage, muscles, and vocal cords. Its structure includes three large unpaired cartilages—the thyroid, cricoid, and epiglottis—and three smaller paired cartilages—the arytenoids,...
Assessment of Airway, Skin Color, and Use of Accessory Muscles
Introduction
The initial evaluation of a patient's respiratory system...
Physical Assessment of the Respiratory Tract IV: Auscultation
Breath Sounds
Breath sounds are categorized into vesicular, bronchovesicular, and bronchial.
Assessment of Ventilation I: Respiratory Rate
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
Respiratory System Abnormal Finding II: Palpation and Auscultation
Palpation Findings
During a respiratory assessment, palpation can reveal several vital abnormalities:

