Aleksandra E Olszewski1, Lisa Shen, Jack J Jiang. 1. Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53706-1532, USA.
Abstract
OBJECTIVES: In acoustic voice analysis, the fact that reproducible methods of sample selection have not been defined impedes research study generalizability and clinical assessment of treatment efficacy. Because perturbation results differ along a single signal, this study sought to establish objective methods of sample selection by use of a moving window to determine the most stable regions of phonation. METHODS: Voice signals obtained from 21 patients affected by laryngeal conditions associated with Parkinson's disease were analyzed to study jitter, shimmer, signal-to-noise ratio, and correlation dimension parameters when various sample selection procedures were used. Objectively selected voice samples were chosen based upon 5%, 10%, and 20% variance from a signal's minimum perturbation value. The stability of these samples, defined by the standard deviations of the acoustic measurements, was compared to the stability of unselected samples and subjectively selected samples. RESULTS: A significant decrease in standard deviation values of acoustic parameters was found in comparing the objectively selected samples (particularly those selected with 5% and 10% variance) to the subjectively selected and unselected samples. CONCLUSIONS: These results suggest that the development of an objective sample selection method may have significant effects on the stability and reliability of acoustic voice measurements.
OBJECTIVES: In acoustic voice analysis, the fact that reproducible methods of sample selection have not been defined impedes research study generalizability and clinical assessment of treatment efficacy. Because perturbation results differ along a single signal, this study sought to establish objective methods of sample selection by use of a moving window to determine the most stable regions of phonation. METHODS: Voice signals obtained from 21 patients affected by laryngeal conditions associated with Parkinson's disease were analyzed to study jitter, shimmer, signal-to-noise ratio, and correlation dimension parameters when various sample selection procedures were used. Objectively selected voice samples were chosen based upon 5%, 10%, and 20% variance from a signal's minimum perturbation value. The stability of these samples, defined by the standard deviations of the acoustic measurements, was compared to the stability of unselected samples and subjectively selected samples. RESULTS: A significant decrease in standard deviation values of acoustic parameters was found in comparing the objectively selected samples (particularly those selected with 5% and 10% variance) to the subjectively selected and unselected samples. CONCLUSIONS: These results suggest that the development of an objective sample selection method may have significant effects on the stability and reliability of acoustic voice measurements.
Authors: Erin E Devine; Erin E Bulleit; Matthew R Hoffman; Timothy M McCulloch; Jack J Jiang Journal: J Speech Lang Hear Res Date: 2012-05-04 Impact factor: 2.297