Objective Assessment Of Voice Quality Research Articles

Exploring The Validity of Acoustic Measurements and Other Voice Assessments

There are different parts of a battery of voice assessments to assess voice functions and voice quality. The objective assessment of voice quality using acoustics is recommended and two measurements such as the Acoustic Voice Quality index, 03.01 (AVQI) and the Acoustic Breathiness Index (ABI) are leading in this domain. The purpose of this study was to verify the validity between these two acoustic measurements and other dimensions of the voice assessments (the Voice Handicap Index-10 (VHI-10) and the laryngeal imaging evaluation of the larynx and vocal folds). We used a retrospective database of 150 participants (37 vocally healthy participants and 113 dysphonic patients). To test the validity between the acoustic measurements and the other voice assessments the concurrent validity and diagnostic precision were analyzed using Pearson correlation coefficient and the receiver operating characteristic (ROC) statistics with likelihood ratios. The VHI-10 score presented moderate-significant correlations with the AVQI and the ABI, r= 0.477, P < 0.001 (r2= 0.228) and r= 0.426, P < 0.001 (r2=0.181), respectively. The larynx alteration presented low-significant correlations with the AVQI (r= 0.362, P < 0.001, r2= 0.131), and ABI (r= 0.371, P < 0.001, r2= 0.138), respectively. The area under the curve (AUC) of ROC was almost reasonable ranging from 0.701 to 0.737; except between ABI and VHI-10 (AUC= 0.689). The highest AUC was between the AVQI and VHI-10 at a threshold of 2.10; the highest specificity was between the ABI and VHI-10 at a threshold of 3.77. However, the lowest sensitivity was between ABI and VHI-10 while the lowest specificity was between the laryngeal diagnosis and the ABI. AVQI and ABI presented significantly lower concurrent validity and diagnostic precision when the reference is not the auditory-perceptual judgment of voice quality. However, AVQI seems to be for some validity aspects a more reasonable classifier of vocal handicap and laryngeal alteration than ABI. Both AVQI and ABI values can broaden their range of assessment for the clinical user, thus showing more relationships between the individual voice examination methods.

The cepstral spectral index of dysphonia, the acoustic voice quality index and the acoustic breathiness index as novel multiparametric indices for acoustic assessment of voice quality.

The objective assessment of voice quality using acoustic measures is an important pillar of voice diagnostics. This article reviews three recent acoustic measures and their clinical use in phoniatrics and laryngology. Two acoustic parameters, the cepstral spectral index of dysphonia (CSID) and the acoustic voice quality index (AVQI), have gained importance as validated multiparametric indices in the objective assessment of hoarseness because they include both continuous speech and sustained vowels. The acoustic breathiness index (ABI), another multiparametric index, assesses breathiness admixture during phonation and identifies it robustly, unaffected by other characteristics of dysphonia such as roughness. Acoustic measurements are useful diagnostic tools when used correctly with an appropriate recording system, consideration of environment and use of software programs. CSID, AVQI and ABI objectively improve the detection of voice quality abnormalities. In addition to their proven validity, their application is simple and their usability for clinicians is high.

Subjective and objective assessment of voice quality in pregnancy.

During pregnancy, voice quality disorders may occur in form of: edema, dryness, nervousness. The aim of the study is subjective and objective evaluation of voice quality in pregnant women. The study included 20 women in the third trimester of pregnancy, age of 20-31 diagnosed at the Department of Clinical Phonoaudiology and Logopedics, Medical University of Bialystok. Subjective assessment has been based on the GRBAS scale. Objective assessment of the vocal organ used the HSDI technique (High Speed Digital Imaging). In the laryngeal visualization, high-speed camera (HS) using rigid endoscope with 90 ° optics has been used. Vibration of vocal folds has been recorded during phonation of vowel &quot;e&quot; at 4000 frames / sec. The glottal closure (GTs), symmetry, regularity and synchronization of vocal folds vibration have been assessed. In estimating the degree of glottal insufficiency, kymography of the larynx has been performed by analyzing the value of Open Quotient (OQ). Objective acoustic evaluation of voice has been also conducted using DiagnoScope Specjalista Program. Hoarseness has been observed in 15 pregnant women, whereas voice fatigability in 20 patients. Using HSDI, the edema of vocal folds in part of the group has been observed. Decreased MPT has been found in all examined women in the third trimester of pregnancy. Hoarseness and fatigability of voice are the most frequent subjective symptoms of voice organ in the third trimester of pregnancy. Decreased MPT is recorded objectively, as well as edema and insufficiency of vocal folds using HSDI technique.

Assessment of acoustic characteristics of voice in patients after injection laryngoplasty with hyaluronan.

Glottal incompetence is one of the most common contributing factors in patients who suffer from dysphonia. One of the different treatment approaches is injection laryngoplasty. The aim of the study was to assess the quality of voice in patients who were treated with hyaluronic acid injection into the vocal fold in the long-term follow-up. The material included 39 patients with dysphonia who were referred for injection augmentation. The studied group included patients with presbyphonia, scar, sulcus, unilateral vocal fold paralysis and with atrophy of the vocal fold. Preoperative and postoperative examination was based on laryngovideostroboscopy. Patients' voice was assessed using the subjective GRBAS scale, and objective evaluation provided by Multidimensional Voice Program (MDVP) was applied. All the patients underwent injection laryngoplasty with hyaluronic acid into the vocal folds. Follow-up examinations were conducted 6, 12 and 24 months postoperatively. Perceptual voice quality assessed with the GRBAS scale was improved and the results were stable in the long-term follow-up periods. MDVP showed a significant statistical improvement within the group of frequency, amplitude and noise parameters. The differences in value between follow-up periods were not statistically significant. Acoustic analysis of voice is a reliable method for objective assessment of voice quality after applied treatment. Injection of the hyaluronic acid into the vocal fold improves the quality of voice in patients suffering from glottic insufficiency.

Accelerometric correlates of nasalized speech in children

Instrumentation-based scoring methods can be used to supplement auditory assessments, providing a more objective assessment of voice quality. One such metric that can be used to assess resonance disorders, the Horii Oral Nasal Coupling Index (HONC), has been shown to successfully separate nasal from nonnasal utterances, but has not been extensively studied in children. We have previously found that using low-pass filtered versions of the nasal accelerometer and microphone signal used in its computation can reduce variability due to vowel placement that is traditionally reported for these scores, and sought to determine whether this reduction in variability would extend to children's speech. We obtained nasal acceleration and speech signals from 26 children, aged 4–9, during the production of various consonant-vowel-consonant tokens and running speech with controlled vowel and consonant loading. HONC scores were compared using broadband and low-frequency portions of these signals. It was found that applying a low-frequency filter reduced the variability of the HONC scores due to vowel type relative to when broadband signals were used, and the scores could discriminate vowels produced in nasal and non-nasal contexts in children with high accuracy. These results demonstrate the potential of HONC scores as an aid in rehabilitating hypernasal speech.

Zastosowanie nowoczesnych fizjoterapeutycznych metod rehabilitacji w leczeniu wybranych postaci dysfonii

Voice quality disorders – dysphonias are the significant problem from therapeutic, social and economic point of view. The routine therapy does not always bring spectacular effects. The important role play the innovative methods supporting therapy of voice quality disorders. PurposeThe aim of the study is to assess the effects of vibratory therapy of the larynx (Medical VR) in patients with hyperfunctional dysphonia and stimulating currents in phonatory exercises (VocaStim–Master) in paralytic dysphonia based on the analysis of parameters of objective assessment of voice quality. Material and methodsForty patients with hyperfunctional dysphonia treated routinely were included in the study. 20 patients apart from the routine therapy were additionally treated using the vibratory therapy of regions of the larynx (Medical VR, CyberBioMed LLC). In group of 40 patients with paralytic dysphonia, in 20 patients the adjuvant therapy by stimulating currents in phonatory exercises (VocaStim–Master, Physiomed) was used. The results of treatment and adjuvant therapy in hyperfunctional and paralytic dysphonia were analyzed based on: MPT, parameters of stroboscopic and acoustic evaluation (F0, Jitter, Shimmer, NHR) and narrow-band spectrography. Results and conclusions: The analysis of the results indicated the usefulness of used parameters of objective assessment of voice quality taking into consideration the diagnostic and therapeutic aspect in hyperfunctional and paralytic dysphonia. Adjuvant vibratory therapy of the larynx in hyperfunctional dysphonia and stimulating currents in phonatory exercises in paralytic dysphonia improved the effectiveness of the therapy, what was confirmed by the analysis of parameters of objective assessment of voice quality.

P.563—The ITU-T Standard for Single-Ended Speech Quality Assessment

Objective voice quality assessment has been the subject of research for many years. Up until very recently, objective models required a copy of the unprocessed signal for estimating the quality of a signal transmitted across a telecommunication network, making live call monitoring impossible. This paper introduces a method for nonintrusive assessment of speech quality for narrow-band telephony, which was approved by the International Telecommunication Union (ITU-T) in May 2004. Essentially based on models of voice production and perception, the algorithm demonstrates good performance on more than 48 subjective experiments representing most distortions that occur on voice networks

Towards estimation of Japanese intelligibility scores using objective voice quality assessment measures

We investigated the use of objective quality measures to estimate the intelligibility of Japanese speech. We initially focused on PESQ (perceptual evaluation of speech quality), which is the state-of-the-art objective assessment method, and can estimate the mean opinion scores (MOS) at an extremely high accuracy. Since we can assume that speech quality is correlated with intelligibility, it should be possible to estimate the intelligibility from the estimated opinion scores or some of its derivatives. We tried to estimate the intelligibility of the Japanese Rhyme Test (DRT). The DRT uses minimal word pairs whose initial phone differs by one phonetic feature. We estimated the MOS of the DRT word samples mixed with noise and tried to correlate this with the measured intelligibility. However, the estimated MOS showed no difference between phonetic features. However, the difference in the estimated MOS between the word pairs seems to differ by a phonetic feature for SNR above 10 dB, which suggests that the estimation of intelligibility by a phonetic feature may be possible. We also plan to selectively use the internal data used to calculate the MOS estimate for better intelligibility estimation.

Pathological voice quality assessment using artificial neural networks

This paper describes a prototype system for the objective assessment of voice quality in patients recovering from various stages of laryngeal cancer. A large database of male subjects steadily phonating the vowel /i/ was used in the study, and the quality of their voices was independently assessed by a speech and language therapist (SALT) according to their seven-point ranking of subjective voice quality. The system extracts salient short-term and long-term time-domain and frequency-domain parameters from impedance (EGG) signals and these are used to train and test an artificial neural network (ANN). Multi-layer perceptron (MLP) ANNs were investigated using various combinations of these parameters, and the best results were obtained using a combination of short-term and long-term parameters, for which an accuracy of 92% was achieved. It is envisaged that this system could be used as an assessment tool, providing a valuable aid to the SALT during clinical evaluation of voice quality.

Objective description of voice quality using the hoarseness diagram

The need for an objective assessment of voice quality can be seen in the increasing use of acoustic analysis methods for clinical diagnosis and research. The hoarseness diagram allows clinicians to objectively describe even highly disturbed or aphonic votes. Its application possibilities are illustrated in three case studies in which changes in voice quality were monitored during voice rehabilitation. The distributions of voice groups that were defined on the basis of specific pathophysiological phonation conditions were then compared for their acoustic differences. The groups comprised various phonation conditions after the resection of laryngeal tumors and different types of laryngeal paralyses. Interpretation of the results suggests a direct correspondence of the hoarseness diagram coordinates and the irregularity of vibration on the one side and the degree of glottal closure on the other. This illustrates the potential usefulness of the hoarseness diagram in a clinical context.

Standards and technology issues in objective voice quality assessment

The need for reliable objective voice quality assessment techniques is growing rapidly. Developers of voice systems and services, procurers of voice communication equipment, and standards organizations all have pressing requirements for voice performance measurement. Many objective assessment measures have been proposed and studied. Currently, an objective technique accurate and robust enough to replace human listeners in all situations does not appear practical. However, the performance of several objective methods (e.g., those being considered by CCITT) is quite promising, and may justify their use in many cases where listener tests can be augmented or replaced completely. Standards defining these objective measures and their intended applications can be expected in the near future. Several important areas of research related to objective voice quality assessment can bde identified: 1. ⊎It is doubtful that even very complex distortion measures will be sufficient to accurately predict voice quality in many real world cases. For example, simple added delay has no effect on perceived quality unless two-way conversation is taking place, in which case the impact can be significant. Other examples include echo, temporal warping (i.e., time varying delay), and even added impulsive noise such as “pops” and “clicks.” A much more involved psychoacoustic model of hearing may be needed to address these impairments, requiring perhaps expert systems or neural network technology to implement the model. 2. ⊎Measures of voice quality are increasingly sought for vocoder, or synthesized, speech. Distortion measures such as discussed in this paper are not directly applicable, since generally no effort is made to reproduce the input voice signal. Only higher level information such as phonemes is transmitted. 3. ⊎Application-specific objective measures may be a better solution than attempting to identify a single parameter for use in all situations. For example, voice transmitted via single sideband radio will be subject to significantly different types of degradation than those found in telephone speech. Perceived quality is also highly dependent on application; an air traffic controller is more concerned with intelligibility than with tonal fidelity, while the opposite may be true for someone using the telephone to call home. The ITS objective method is one approach to this, by allowing a new parameter set and a new training database to be invoked for new applications. These areas and others will see increasing interest as technical and economic pressure continues to build for dependable objective voice quality assessment techniques. Recommendations expected soon from CCITT will likely represent only a partial solution to this difficult problem, and continued research is crucial to develop more robust and reliable techniques.