Acoustic analysis of voice signal: Comparison of four applications software

Test-Retest Reliability and Discriminatory Power of Multi-Dimensional Voice Analysis Program (MDVP)

OBJECTIVES

The objectives of this study were to evaluate and compare the test-retest reliability of acoustic parameters (jitter [%], shimmer [%], noise-to-harmonic ratio (NHR), and voice turbulence index (VTI)) by using multidimensional voice program (MDVP), and to detect the discriminatory power of the acoustic measures with respect to dysphonic voices and normal voices.

DESIGN, SETTING, PARTICIPANTS, AND METHODS

Fifty-four (25 male and 29 female) participants with voice disorders and fifty-one (27 male and 24 female) participants with normal voices were enrolled in this study. They were assessed by anamnesis, visual examination, auditory perceptual assessment (GRBAS), and acoustic measurements. The intraclass correlation coefficient was used to determine the test-retest reliability. The effect size (d value) and p value obtained from the t-test were used to determine the discriminatory power.

RESULTS

In the normal group, good reliability was observed for jitter, shimmer, and NHR, and moderate reliability was observed for VTI. With regard to the dysphonic group, jitter, shimmer, and VTI were moderately reliable, and the NHR had good reliability. Meanwhile, the discriminatory powers of jitter and shimmer were evaluated as 'medium', and those of NHR and VTI as 'small'.

CONCLUSIONS

The reliability and discriminatory powers of our acoustic measures were high compared with most other studies. Their level of reliability and discriminatory power can be maximised by using stringent rules. However, attaining an excellent level of reliability and discriminatory seems infeasible power owing to the variable characteristic of voice. Therefore, acoustic measures should be adopted as a complementary tool.

A Comparison of Healthy and Disordered Voices Using Multi-Dimensional Voice Program, Praat, and TF32

PURPOSE

Instrumental voice assessment plays a critical role in identifying vocal issues and for documenting treatment outcomes. The reported voice data, however, are sensitive to the algorithm used by each acoustic analysis software program (AASP) to analyze the corresponding waveform. In the present study, five acoustic measures were compared across healthy speakers and speakers with dysphonia for three AASPs commonly used in research, education, and clinical practice: Multidimensional Voice Program (MDVP) by Computerized Speech Lab, Praat, and TF32.

MATERIALS AND METHODS

Sustained vowel phonations for the quantal vowels /ɑ/, /i/, and /u/ were analyzed for 80 speakers with organic dysphonia and 60 age- and sex-matched healthy controls. Descriptive, inferential, and correlation data are reported for mean fundamental frequency (mean F0), standard deviation of fundamental frequency (SD F0), short-term perturbation measures of jitter and shimmer, and harmonic-to-noise ratio (HNR).

RESULTS

The present study replicated previous findings of interprogram differences for healthy speakers, with MDVP consistently yielding higher values than Praat and TF32 for SD F0, jitter, and shimmer and lower values for HNR. Similar, but magnified patterns of results were observed for speakers with dysphonia.

CONCLUSION

The variation observed across programs calls into question the validity in comparing voice outcomes reported by one AASP to those previously obtained by another, particularly for acoustic signals with aperiodic components that are commonly present in disordered voices. It is advised that waveforms be visually inspected prior to conducting acoustic analysis, and that voice outcomes not be combined or compared across AASPs.

Vocal profile of 46,XX individuals with congenital adrenal hyperplasia

PURPOSE

Describe the vocal profile of 46,XX congenital adrenal hyperplasia (CAH) patients followed up at the Genetics Outpatient Clinic of the Federal University Bahia (GOC-UFBA).

METHODS

This is a descriptive, exploratory, cross-sectional study. The study sample consisted of 28 volunteers: 14 individuals diagnosed with CAH, followed up by the multiprofessional team of the GOC-UFBA, and 14 46,XX individuals without vocal changes and endocrine and/or genetic pathologies. Voice sample collection was performed individually in a quiet environment with participants properly seated. Acoustic (PRAAT program) and auditory-perceptual (Consensus Auditory-Perceptual Evaluation of Voice - CAPE-V) analyses were conducted.

RESULTS

In the qualitative assessment of pitch, eight (61.54%) patients in the CAH group showed low vocal pattern and eight (61.54%) individuals in the group without CAH presented high vocal pattern. There were statistically significant differences between the groups only for the following vocal attributes of the CAPE-V: overall severity (p=0.01), roughness (p=0.00), and pitch (p=0.01). No statistically significant difference was observed in the other acoustic parameters investigated (p>0.05).

CONCLUSION

The present study demonstrated that 46,XX CAH individuals, even when submitted to hormone therapy, present rough, low, deviant voice.

A Field-Based Approach to Establish Normative Acoustic Data for Healthy Female Voices

Purpose The primary aim of this study was to obtain high-quality acoustic normative data in natural field environments for female voices. A secondary aim was to examine acoustic measurement variability in field environments. Method This study employed a within-subject repeated-measures experimental design that included 45 young female adults with normal voices. Participants were stratified by age (18-23, 24-29, and 30-35 years). After initial evaluation and instruction, participants completed voice recordings during seven consecutive days using a standard protocol, including both connected speech and sustained vowels. Thirty-two cepstral-, spectral-, and time-based acoustic measures were acquired using Praat and the Analysis of Dysphonia in Speech and Voice. Results Among the 958 total recordings, greater than 90% satisfied inclusion criteria based on protocol compliance, peak clipping, and signal-to-noise ratio. Significant differences were observed for age (p < .05). For 19 acoustic measures, values improved significantly as signal-to-noise ratio increased. Cepstral- and spectral-based measures demonstrated less measurement variability as compared with time-based measures. Conclusions With adequate training, field audio recordings represent a viable option for clinical voice management. The significant age effects observed in this study support the need for more specific criteria when collecting and applying normative data. Cepstral- and spectral-based measures demonstrated the least measurement variability. This study provides additional evidence for multiparameter acoustic voice measurement, specifically toward ecologically valid sampling in natural environments. Future studies should expand on these findings in other populations with normal and disordered voices.

Acoustic parameters of voice in typically developing children ages 4-19 years

OBJECTIVES

Report data on acoustic measures of voice in sustained vowels produced by typically developing children, aged 4-19 years, to add to the cross-sectional reference values in a pediatric database.

METHODS

Recordings of sustained vowel/ɑ/phonation were obtained from 158 children (80 males, 78 females) aged 4-19 years who were judged to be typically developing with respect to speech and voice. Acoustic analyses were performed with the Multidimensional Voice Program (MDVP™) and the Analysis of Dysphonia in Speech and Voice (ADSV™), both from Pentax Medical.

RESULTS

Values from both MDVP and ADSV are reported for children in the following age cohorts: 4-6 years, 7-9 years, 10-12 years, 13-15 years, and 16-19 years.

CONCLUSION

The data in this study complement previously published data and contribute to a pediatric reference database useful for research and for clinical practice related to children's voice. Acoustic parameters most sensitive to age and sex are identified.

Effects of Fundamental Frequency, Vocal Intensity, Sample Duration, and Vowel Context in Cepstral and Spectral Measures of Dysphonic Voices

Purpose Smoothed cepstral peak prominence (CPPS) and harmonics-to-noise ratio (HNR) are acoustic measures related to the periodicity, harmonicity, and noise components of an acoustic signal. To date, there is little evidence about the advantages of CPPS over HNR in voice diagnostics. Recent studies indicate that voice fundamental frequency (F0) and intensity (sound pressure level [SPL]), sample duration (DUR), vowel context (speech vs. sustained phonation), and syllable stress (SS) may influence CPPS and HNR results. The scope of this work was to investigate the effects of voice F0 and SPL, DUR, SS, and token on CPPS and HNR in dysphonic voices. Method In this retrospective study, 27 Brazilian Portuguese speakers with voice disorders were investigated. Recordings of sustained vowels (SVs) /a:/ and manually extracted vowels (EVs) /a/ from Consensus Auditory-Perceptual Evaluation of Voice sentences were acoustically analyzed with the Praat program. Results There was a highly significant effect of F0, SPL, and DUR on both CPPS and HNR (p < .001), whereas SS and vowel context significantly affected CPPS only (p < .05). Higher SPL, F0, and lower DUR were related to higher CPPS and HNR. SVs moderately-to-highly correlated with EVs for CPPS, whereas HNR had few and moderate correlations. In addition, CPPS and HNR highly correlated in SVs and seven EVs (p < .05). Conclusion Speaking prosodic variations of F0, SPL, and DUR influenced both CPPS and HNR measures and led to acoustic differences between sustained and excised vowels, especially in CPPS. Vowel context, prosodic factors, and token type should be controlled for in clinical acoustic voice assessment.

Is there an improvement on acoustic voice parameters in patients with bilateral vocal fold nodules after voice therapy? a meta-analysis

BACKGROUND/OBJECTIVE

The aim of this study is to estimate the effect of voice therapy intervention in adults with vocal fold nodules, on three acoustic voice parameters (fundamental frequency_, jitter and shimmer). The purpose of this meta-analysis is to present evidence based on literature regarding objective acoustic voice parameters changes, after voice therapy, in patients with bilateral VFNs. A pooled statistical analysis comparing pre- and post-therapy measurements of three acoustic voice parameters (average F0, % jitter and % shimmer) were performed.

METHODS

A literature review was performed by searching studies in adults, with bilateral vocal fold nodules who received voice therapy, and where voice quality was evaluated quantitatively using acoustic analysis, before and after treatment. Meta-analysis was performed using random-effects model. PubMed, CINAHL, CENTRAL and Web of Science were searched for retrospective and prospective cohort, cross-sectional and case-control with comparative studies in adults published between January/1995 and March/2019 and English written. Search terms used were: intervention, therapy, vocal, voice, nodules, bilateral, multidimensional assessment, acoustic and analysis.

RESULTS

Overall 1950 articles were identified. After removing repeated articles and conducting screening stages using inclusion and exclusion criteria, a total of four studies were selected with 147 participants for the meta-analysis. The pooled results analysis showed a statistically significant effect in two acoustic parameters after voice therapy: (1) F0 [increased mean difference post-therapy was 33.00 Hz (95% CI 20.26-45.74, p < 0.001)] and (2) jitter (%) [decreased mean difference post-therapy was 0.59% (95% CI 0.23-0.94%, p = 0.001)]. In addition, a non-statistically significant effect in shimmer (%) [decreased mean difference post-therapy was 2.98% (95% CI - 0.03-6.00, p = 0.052)].

CONCLUSION

Acoustic analysis has a clinical role in patients with vocal fold nodules, by objectively assessing and providing data on the effect of voice therapy in voice acoustic parameters. This meta-analysis has shown that patients with vocal fold nodules improved their acoustic voice parameters after receiving voice therapy.