Perceptual Evaluation Of Voice Quality Research Articles

A Comparison of Voice Quality Ratings Made by Japanese and American Listeners Using the GRBAS Scale

The GRBAS scale is a widely used method for perceptual evaluation of voice quality. Two linguistically diverse groups of listeners (Japanese and American) rated 35 voice samples using the GRBAS scale. The ratings obtained from the two groups were compared to determine if the different linguistic background affected the use of the GRBAS scale. Results show that there are no significant differences between the Japanese and American listeners in the use of the Grade, Roughness and Breathiness scales. Ratings on the Asthenia and Strain scales, however, were different between the two groups of listeners. Despite these discrepancies, the GRBAS scale may be an excellent tool for perceptual evaluation of voice quality by linguistically diverse groups.

Communicative Suitability of Voice Following Radiotherapy for T1 Glottic Carcinoma: Testing the Reliability of a Rating Instrument

The objective of the study was to determine whether a communicative suitability rating instrument could be used in a meaningful way to assess functionality of voice following radiotherapy for T1 glottic cancer. Seventeen naive listeners judged the suitability of voice of a patient group with T1 glottic carcinoma ( n = 20) just before treatment, a group of patients ( n = 40) after radiotherapy, and a matched control group ( n = 20) of normal speakers. Listeners rated suitability on a 10-point scale for 10 speaking situations, which supposedly make different demands. In order to validate scores on communicative suitability, ratings were related to perceptual voice quality evaluations and videolaryngostroboscopic evaluations. Results indicate that the concept of measuring listener judgments of communicative suitability of voice is basically sound. Raters are reliable and can discriminate between groups of normal and pathological voices. Patients with T1 glottic carcinoma (assessed before the start of treatment) have on average the least suitable voices. Following radiotherapy suitability is, on average, improved, but does not approach the suitability of normal voices. Ratings on communicative suitability were clearly related to perceptual voice quality aspects and videolaryngostroboscopic evaluations. A subset of three communicative suitability rating scales is recommended as part of the protocol for evaluating voice outcome after radiotherapy for early glottic cancer, besides perceptual evaluation of voice quality by trained and naive raters, videolaryngostroboscopy, acoustical analyses, and self-ratings of vocal performance.

Autologous transplantation of fascia into the vocal fold as a treatment for recurrent nerve paralysis.

To apply the technique of autologous transplantation of fascia graft into the vocal fold for glottal insufficiency due to recurrent nerve paralysis and to evaluate the results in eight patients who underwent the procedure. Technical modifications were made in transplantation of the temporal fascia into the paralyzed vocal fold. Eight patients underwent the surgery, and their phonatory function was examined preoperatively and postoperatively. The following surgical techniques were applied to prevent the falling-off of the graft: 1) a roll-shaped fascia graft was prepared before the transplantation and 2) a pocket was made within the lamina propria mucosa using a newly devised special elevator. The maximum phonation time and airflow rate during sustained phonation (in four cases) were measured, and perceptual evaluation of voice quality was made using the GRBAS scale by speech pathologists before and after the surgery. All the cases showed no evidence of falling-off of the graft. Elongation of the maximum phonation time and improvement in voice quality were obtained in all cases postoperatively. The method proved to be useful for the treatment of glottal insufficiency due to recurrent nerve paralysis.

Quantitative videofluoroscopy: a new evaluation tool for tracheoesophageal voice production

Introduction. The objective was to gain insight into the relationship between tracheoesophageal voice quality and anatomical and morphological characteristics of the neoglottis, using perceptual evaluation of voice quality (good/reasonable/poor) and an evaluation protocol for videofluoroscopy recordings of the neoglottis (visual assessment and quantitative measures on digitized images).1 Methods. Thirty-nine laryngectomized patients (nine also underwent pharyngeal and/or oesophageal reconstruction) (29 men and 10 women, aged 47–82 years, mean 67) were studied. Perceptual evaluations were performed on read-aloud text; evaluation of videofluoroscopy recordings was undertaken at rest and during phonation. Results. Voice quality is related to tonicity of the neoglottis and appearance of a neoglottic bar during phonation. In a ‘good’ voice, there is always a visible neoglottic bar and never hypotonicity. Furthermore, voice quality is related to the ratio maximal subneoglottic distance at rest/during phonation (larger in ‘good’ speakers), minimal distance during phonation and minimal distance at rest (smaller in ‘good’ speakers). Conclusion. Anatomical and morphological characteristics of the neoglottis are related to tracheoesophageal voice quality. The quantitative measures enable more standardized evaluation of neoglottic characteristics.

Formal perceptual evaluation of voice quality in the United Kingdom

This document is a position statement on the formal perceptual evaluation of voice quality in the United Kingdom (UK). It addresses a number of clinical issues pertaining to the complexity of voice quality analysis. There is also a brief description of the three formal perceptual protocols most commonly used in the UK: The Vocal Profile Analysis (VPA), GRBAS and The Buffalo III Voice Profile. Potential clinical problems with perceptual voice quality evaluation are highlighted. Problems associated with the lack of defined terminology, limitless variety of voice quality, general lack of reliability data and difficulties in determining specificity and sensitivity are discussed. A practical guide for selecting an evaluation scheme is described. The conclusion is that the GRBAS scheme should be recommended as the absolute minimum standard for practising UK voice clinicians. However, there is a clear need to develop a more satisfactory perceptual rating scheme that is clinically realistic, theoretically sound, internationally acceptable and has proven reliability.

Analysis of voice changes after thyroplasty using linear predictive coding.

Objective measurement of vocal quality is difficult in patients with severe voice disorders. Improved success has been reported using a modeling technique known as linear predictive coding. This technique uses an inverse filter to estimate a glottic excitation signal. The pitch amplitude is defined as the height of the first peak of the autocorrelation of the glottic excitation signal. In this study linear predictive coding was used to analyze voice disorders in patients with vocal fold immobility. Voice recordings were made in 16 patients undergoing vocal fold medialization and 10 patients who had no surgical procedure between measurements. The voice quality was rated by three speech pathologists. Five acoustic parameters were calculated from the samples. The best agreement with the listeners' perceptual analysis was achieved using the pitch amplitude. Both pitch amplitude and the perceptual ratings of voice quality improved in patients undergoing vocal fold medialization. Therefore the linear model of speech production and inverse filtering are useful in measuring vocal quality in patients with vocal fold immobility.

Test-retest study of the GRBAS scale: Influence of experience and professional background on perceptual rating of voice quality

Perceptual evaluation was performed by means of the GRBAS scale for a series of nine pathological voice samples that were presented twice to a group of 23 judges, consisting of experienced and inexperienced otolaryngologists (ENTs) and speech-language pathologists (S/LPs). The time interval between ratings was 14 days. Test-retest reliability was moderate. The best agreement between the observers was obtained for the G (grade) parameter and the worst for the S (strained) parameter. Considering the medians of the GRBAS ratings, no significant influence was measured for level of experience or professional background. Yet, based on means, the results show that professional background has a greater impact on perceptual rating than experience.

Perceptual Evaluation of Voice Quality

The reliability of listeners' ratings of voice quality is a central issue in voice research because of the clinical primacy of such ratings and because they are the standard against which other measures are evaluated. However, an extensive literature review indicates that both intrarater and interrater reliability fluctuate greatly from study to study. Further, our own data indicate that ratings of vocal roughness vary widely across individual clinicians, with a single voice often receiving nearly the full range of possible ratings. No model or theoretical framework currently exists to explain these variations, although such a model might guide development of efficient, valid, and standardized clinical protocols for voice evaluation. We propose a theoretical framework that attributes variability in ratings to several sources (including listeners' backgrounds and biases, the task used to gather ratings, interactions between listeners and tasks, and random error). This framework may guide development of new clinical voice and speech evaluation protocols, ultimately leading to more reliable perceptual ratings and a better understanding of the perceptual qualities of pathological voices.

EMG biofeedback as a function of voice-quality change.

Changes in electromyography (EMG) accompanying changes in voice quality are reported. Audio recordings were obtained from four normal speakers during production of sustained vowels, counting and reading. These were uttered first in a normal voice and then in a voluntarily produced harsh voice. Perceptual ratings of voice quality of these utterances were made and compared to averaged EMG values obtained during the productions. The surface electrode placement remained unchanged over each of the cricothyroid areas for both normal and harsh voice. For one of the speakers, changes in EMG paralleled changes in vocal quality. For the other three, changes in EMG were variable, and sometimes minimal, in comparison to changes in voice. The results are discussed in relation to the clinical use of EMG for voice disorders.