Perceptual analysis in different voice samples: agreement and reliability

The influence of listener experience, measurement scale and speech task on the reliability of auditory-perceptual evaluation of vocal quality

PURPOSE

To assess the influence of the listener experience, measurement scales and the type of speech task on the auditory-perceptual evaluation of the overall severity (OS) of voice deviation and the predominant type of voice (rough, breathy or strain).

METHODS

22 listeners, divided into four groups participated in the study: speech-language pathologist specialized in voice (SLP-V), SLP non specialized in voice (SLP-NV), graduate students with auditory-perceptual analysis training (GS-T), and graduate students without auditory-perceptual analysis training (GS-U). The subjects rated the OS of voice deviation and the predominant type of voice of 44 voices by visual analog scale (VAS) and the numerical scale (score "G" from GRBAS), corresponding to six speech tasks such as sustained vowel /a/ and /ɛ/, sentences, number counting, running speech, and all five previous tasks together.

RESULTS

Sentences obtained the best interrater reliability in each group, using both VAS and GRBAS. SLP-NV group demonstrated the best interrater reliability in OS judgment in different speech tasks using VAS or GRBAS. Sustained vowel (/a/ and /ɛ/) and running speech obtained the best interrater reliability among the groups of listeners in judging the predominant vocal quality. GS-T group got the best result of interrater reliability in judging the predominant vocal quality.

CONCLUSION

The time of experience in the auditory-perceptual judgment of the voice, the type of training to which they were submitted, and the type of speech task influence the reliability of the auditory-perceptual evaluation of vocal quality.

Phonatory Tasks and Outcome Measures for Assessing Vocal Fatigue: A Scoping Review

OBJECTIVES

To map the phonatory tasks and the result measures used to evaluate vocal fatigue in vocally healthy individuals.

METHODS

This is a scoping review based on the following research question: What are the phonatory tasks and outcome measures used for the evaluation of vocal fatigue in vocally healthy individuals? The construction of the search strategy followed the PCC strategy; population: vocally healthy adult individuals; concept: phonatory tasks and vocal evaluation measures; and context: vocal fatigue. The search was performed electronically in the databases Medline (PubMed), LILACS (BVS), SCOPUS (Elsevier), Web of Science (Clarivate), EMBASE, and COCHRANE. A manual search in the references of the selected articles and in the journal with the highest number of publications was also performed. The selection of articles was based on reading the titles, abstracts, and full text, applying the eligibility criteria. The selected articles were related to the evaluation of vocal fatigue in healthy individuals from a predetermined vocal load task. Data regarding the characteristics of the publication, sample, phonatory tasks, and outcomes were extracted. The results were presented in a descriptive format, due to a frequency distribution analysis.

RESULTS

In total, 3756 studies were identified during the search, of which 60 were selected. The most used vocal load activity was the reading task, with duration ranging from 46 to 120 minutes. The (1) sustained vowel /a/ and (2) the reading of texts and phrases, both in usual intensity and frequency without the interference of the researcher, were the most used evaluation tasks. The most used outcome measures are the following: (1) acoustic parameters-fundamental frequency [fo] (mean, variance), sound pressure level (mean), local jitter (%), local shimmer (%), cepstral peak prominence (mean); (2) vocal self-assessment by the validated instruments-Perceived Phonatory Effort Scale, Visual Analog Scale, Borg-CR-10 Scale.

CONCLUSIONS

There is a diversity of phonatory tasks and outcome measures recurrently used in scientific articles to evaluate the signs of vocal fatigue in vocally healthy individuals. The most used vocal sample to evaluate vocal fatigue was the sustained vowel /a/ in habitual intensity and frequency without the interference of the researcher. The most frequently reported outcome measures for the assessment of immediate vocal fatigue effects were the acoustic analysis and vocal self-assessment.

Biofeedback in dysphonia - progress and challenges

Introduction

There is evidence that all the complex machinery involved in speech acts along with the auditory system, and their adjustments can be altered.

Objective

To present the evidence of biofeedback application for treatment of vocal disorders, emphasizing the muscle tension dysphonia.

Methods

A systematic review was conducted in Scielo, Lilacs, PubMed and Web of Sciences databases, using the combination of descriptors, and admitting as inclusion criteria: articles published in journals with editorial committee, reporting cases or experimental or quasi-experimental research on the use of biofeedback in real time as additional source of treatment monitoring of muscle tension dysphonia or for vocal training.

Results

Thirty-three articles were identified in databases, and seven were included in the qualitative synthesis. The beginning of electromyographic biofeedback studies applied to speech therapy were promising and pointed to a new method that enabled good results in muscle tension dysphonia. Nonetheless, the discussion of the results lacked physiological evidence that could serve as their basis. The search for such explanations has become a challenge for speech therapists, and determined two research lines: one dedicated to the improvement of the electromyographic biofeedback methodology for voice disorders, to reduce confounding variables, and the other dedicated to the research of neural processes involved in changing the muscle engram of normal and dysphonic patients.

Conclusion

There is evidence that the electromyographic biofeedback promotes changes in the neural networks responsible for speech, and can change behavior for vocal emissions with quality.

Comparison of Rater's reliability on perceptual evaluation of different types of voice sample

OBJECTIVE/HYPOTHESIS

The objective of this study was to determine whether different types of voice samples affect rater reliability and which type of sample can be rated most reliably, with particular reference to two types of connected speech-passage reading and conversational speech.

STUDY DESIGN

Prospective reliability study.

METHODS

One hundred fifty voice samples from 40 speakers were presented to 14 speech pathologists experienced in managing voice disorders. Each speaker contributed three types of voice samples: sustained vowels, passage reading, and conversational speech. Ratings were made on four vocal parameters--overall severity, roughness, breathiness, and strain--on a 10-point equal-appearing interval scale.

RESULTS

Differences in intrarater reliability across the three types of voice samples were noted. Higher intrarater reliability was achieved with connected speech than with sustained vowel samples. Interrater reliability showed no statistically significant difference across the three types but increased with the severity of dysphonia.

CONCLUSIONS

This study reveals that raters give internally more reliable ratings for connected speech samples. Results also indicate that voices with severe disorders appear to be rated more reliably.

An exploration of listener variability in intelligibility judgments

PURPOSE

This study was designed to assess potential contributors to listener variability in judgments of intelligibility.

METHOD

A total of 228 unfamiliar everyday listeners judged speech samples from 3 individuals with dysarthria. Samples were the single-word phonetic contrast test, the Sentence Intelligibility Test, an unpredictable sentence intelligibility test, and conversational speech.

RESULTS

Across speakers, significant variability was found for all samples except the phonetic contrast test. Across tasks, significant variability was found for all speakers. There were no significant differences in age, gender, or education between the highest and lowest scoring listeners on the phonetic contrast test.

CONCLUSIONS

These findings suggest that seemingly objective intelligibility tests are subject to a number of factors that affect scores.

The Effect of Speaking Task on Perceptual Judgment of the Severity of Dysphonic Voice

This study investigated the effect of speaking task on auditory-perceptual judgment of the severity of dysphonia. Three speech-language pathologists experienced in evaluating of disordered voices rated 29 recorded speakers, each of whom produced speech elicited via the same three tasks: sustained vowel /a/, oral reading of a standard passage, and connected speech describing a standard picture. Stimuli were played in sound field, and raters used direct magnitude estimation with a visual analog scale. A repeated measures analysis of variance (ANOVA) revealed a statistically significant (P < .05) effect of speaking task, with post hoc analyses that indicate a statistically significant difference between ratings for the sustained vowel versus connected speech elicited via picture description (P < .05). No statistically significant difference in ratings was found between oral reading and picture description or between oral reading and the sustained vowel. The ANOVA also revealed a statistically significant difference among raters (P < 0.001), but no statistically significant task by rater interaction. Possible reasons for an effect of speaking task are discussed. Also, the implications of one task for determination of dysphonic severity are discussed, as is the possibility of a task effect when determining other clinically useful vocal parameters.