The Dysphonia Severity Index (DSI)-Normative Values. Systematic Review and Meta-Analysis

Multidimensional Comparison of Immediate Effect of Semi-Occluded Vocal Tract Exercises and Vocal Facilitating Techniques on Vocal Function of Speech-Language Pathologists With Vocal Fatigue: A Randomized Clinical Trial

OBJECTIVES

Vocal fatigue is a common hyperfunctional voice condition, particularly among speech-language pathologists (SLPs), due to their high vocal demands. This study compared the immediate effects of semi-occluded vocal tract (SOVT) exercises and vocal facilitating techniques (VFTs) on the vocal function of SLPs with vocal fatigue, emphasizing multidimensional voice assessments.

STUDY DESIGN

Single-blind randomized clinical trial.

METHODS

Twenty-six SLPs and senior speech therapy students with vocal fatigue were randomly assigned to SOVT or VFT groups. Participants performed four techniques for approximately 40 minutes. Vocal outcomes, including single-dimension (jitter, shimmer, harmonic-to-noise ratio [HNR], and Cepstral Peak Prominence Smoothed [CPPS]) and multiparametric (Acoustic Voice Quality Index [AVQI], Acoustic Breathiness Index [ABI]) acoustic measures, as well as maximum performance task and auditory-perceptual parameters, were evaluated before and immediately after treatment. Within-group and between-group comparisons were conducted.

RESULTS

SOVT exercises significantly improved single-dimension acoustic parameters, including jitter, shimmer, and HNR and auditory-perceptual dysphonia severity within the group (P < 0.05). Between-group analysis showed a greater reduction in jitter and auditory-perceptual severity in the SOVT group compared with the VFT group (P < 0.05). However, multiparametric acoustic indices, including AVQI and ABI, showed no significant changes in either group, suggesting that longer interventions may be necessary to impact connected speech.

CONCLUSIONS

SOVT exercises showed immediate improvements in acoustic and auditory-perceptual measures for SLPs with vocal fatigue, making them a promising short-term intervention. However, while sustained vowel analysis revealed significant changes, connected speech analysis did not show similar improvements, highlighting the importance of assessing real-world vocal function. In contrast, VFT techniques likely require longer durations to yield significant effects. Future research should explore extended treatments with multiparametric measures to better understand their efficacy for professional voice users.

Comparison of Two Multiparameter Acoustic Voice Outcome Indices in the Treatment of Hyperfunctional Voice Disorders: Dysphonia Severity Index and Acoustic Voice Quality Index

INTRODUCTION

The Dysphonia Severity Index (DSI) and Acoustic Voice Quality Index (AVQI) are the two widely used multiparameter acoustic instrumented indices that estimate dysphonia severity and track treatment outcomes. This study compared the performance of these two indices in identifying voice quality changes with eclectic voice therapy in individuals with hyperfunctional voice disorders (HFVD).

METHOD

Twenty individuals with HFVD including eight males and 13 females in the age range of 20-55 years received an eclectic voice therapy program named the Comprehensive Voice Habilitation Program. All the participants attended 15 sessions of voice therapy. DSI and AVQI measures were obtained at the baseline, immediate post therapy, 15 days post therapy (follow-up 1), and 60 days post therapy (follow-up 2). Repeated measures analysis of variance was performed to verify whether there were any differences between the time points for dependent variables DSI and AVQI. The effect sizes obtained for the DSI and AVQI measures were also noted.

RESULTS

A significant difference was obtained between the baseline and post therapy, follow-up 1 and follow-up 2 for AVQI measure with a very large effect size, ηp2 = 0.451. In contrast, DSI showed a significant difference only between the baseline and follow-up 1 with effect size, ηp2 = 0.187.

CONCLUSIONS

The results of this study confirmed that both DSI and AVQI were effective in tracking the changes in the severity of dysphonia. However, when compared, AVQI appeared to be more sensitive than DSI in potentially reflecting the effect of eclectic voice therapy in HFVD.

A Comparison of the Dysphonia Severity Index and Singing Voice Handicap Index Between Trained and Untrained Male Iranian Traditional Singers

OBJECTIVES

This study aimed to compare trained and untrained Iranian traditional singers on the Dysphonia Severity Index (DSI) and the Singing Voice Handicap Index. The second objective was to examine the relationship between the DSI and Persian version of the Singing Voice Handicap Index (P-SVHI) scores in each group of trained and untrained Iranian traditional singers.

STUDY DESIGN

This study is a comparative cross-sectional study.

METHODS

This study included 17 trained male Iranian traditional singers who were compared with 17 untrained ones who were matched in terms of age. The P-SVHI was completed by trained and untrained Iranian traditional singers. Measures of jitter, lowest intensity, highest phonational frequency, and maximum phonation time (MPT) were obtained from each participant. The DSI scores were calculated using these values.

RESULTS

Trained male traditional singers had an average age of 33.76 ± 7.45 years, 3.24 ± 1.85 hours of daily practice, 5.24 ± 3.78 years of training, 3.06 ± 2.65 no. of professional performances, and untrained singers had an average age of 32.76 ± 12.92 years, 1.53 ± 1.17 hours of daily practice, and 0.88 ± 1.65 no. of professional performances. Trained singers had lower P-SVHI scores and sub-scores, longer MPT, higher F0 high, lower jitter, and lower I low, resulting in higher DSI values (P < 0.05). There was no significant correlation between P-SVHI scores and DSI values in each group of trained and untrained Iranian traditional singers (P > 0.05).

CONCLUSIONS

The results of this study show that the vocal abilities of professional vocalists are enhanced through voice training (higher DSI scores in trained singers vs untrained ones). Voice training can also help to lessen the perception of a handicap related to the singing voice. Hence, it may be necessary to consider alternative norms for the DSI and P-SVHI when administering them to patients who have undergone guided vocal training, such as voice/singing lessons. The current research indicates that the perception of singing voice handicap and DSI values are two distinct characteristics that do not have a significant correlation.

Accuracy Analysis of the Multiparametric Acoustic Voice Indices, the VWI, AVQI, ABI, and DSI Measures, in Differentiating between Normal and Dysphonic Voices

The study aimed to investigate and compare the accuracy and robustness of the multiparametric acoustic voice indices (MAVIs), namely the Dysphonia Severity Index (DSI), Acoustic Voice Quality Index (AVQI), Acoustic Breathiness Index (ABI), and Voice Wellness Index (VWI) measures in differentiating normal and dysphonic voices. The study group consisted of 129 adult individuals including 49 with normal voices and 80 patients with pathological voices. The diagnostic accuracy of the investigated MAVI in differentiating between normal and pathological voices was assessed using receiver operating characteristics (ROC). Moderate to strong positive linear correlations were observed between different MAVIs. The ROC statistical analysis revealed that all used measurements manifested in a high level of accuracy (area under the curve (AUC) of 0.80 and greater) and an acceptable level of sensitivity and specificity in discriminating between normal and pathological voices. However, with AUC 0.99, the VWI demonstrated the highest diagnostic accuracy. The highest Youden index equaled 0.93, revealing that a VWI cut-off of 4.45 corresponds with highly acceptable sensitivity (97.50%) and specificity (95.92%). In conclusion, the VWI was found to be beneficial in describing differences in voice quality status and discriminating between normal and dysphonic voices based on clinical diagnosis, i.e., dysphonia type, implying the VWI's reliable voice screening potential.

The Occurrence of Laryngeal Pathologies in a Treatment-Seeking Pediatric Population

OBJECTIVES

The purpose of this study was to 1) describe the age- and sex-specific occurrence of laryngeal pathologies in a treatment-seeking pediatric population in the voice unit of Ghent University Hospital, Belgium, and 2) describe this population in terms of vocal parameters, vocal complaints, influencing factors, and treatment history and recommendation.

STUDY DESIGN

Retrospective, observational study.

METHODS

All patient records were analyzed for children (0-18 years) who consulted the ear, nose, and throat department of Ghent University Hospital for the first time between July 2015 and June 2021 with complaints of dysphonia. In total, 103 children (66 males, 37 females) with a mean age of 10.01 years (SD: 3.4, range 3.93-17.96) were included in this study. Laryngeal pathology was diagnosed using a flexible videolaryngo(strobo)scopy. The influence of age and sex on laryngeal etiology (organic/functional voice disorder) was examined using a Welch-modified t test and a Fisher's exact test, respectively.

RESULTS

Organic lesions were observed in 77.7% of the participants, with vocal fold nodules (VFNs) being the most common diagnosis (66.0%). A functional voice disorder was diagnosed in 22.3% of the children. Children with a functional voice disorder are significantly older than children with an organic voice disorder. There was no statistically significant difference between males and females in laryngeal etiology. Mean dysphonia severity index was -2.7 (SD: 3.2, range -9.3 to +3.7), the mean acoustic voice quality index 4.70 (SD: 1.5, range 2.35-8.27), and the mean pediatric voice handicap index 29.8 (SD: 13.6, range 5-60). The occurrence of vocal misuse was mentioned in 80.6% of the patient records.

CONCLUSION

Organic voice disorders, especially VFNs, are predominant in treatment-seeking children with dysphonia. Functional voice disorders become more common with increasing age during childhood. A disordered vocal quality, reduced vocal capabilities and reduced voice-related quality of life were found.

Advances in Clinical Voice Quality Analysis with VOXplot

BACKGROUND

The assessment of voice quality can be evaluated perceptually with standard clinical practice, also including acoustic evaluation of digital voice recordings to validate and further interpret perceptual judgments. The goal of the present study was to determine the strongest acoustic voice quality parameters for perceived hoarseness and breathiness when analyzing the sustained vowel [a:] using a new clinical acoustic tool, the VOXplot software.

METHODS

A total of 218 voice samples of individuals with and without voice disorders were applied to perceptual and acoustic analyses. Overall, 13 single acoustic parameters were included to determine validity aspects in relation to perceptions of hoarseness and breathiness.

RESULTS

Four single acoustic measures could be clearly associated with perceptions of hoarseness or breathiness. For hoarseness, the harmonics-to-noise ratio (HNR) and pitch perturbation quotient with a smoothing factor of five periods (PPQ5), and, for breathiness, the smoothed cepstral peak prominence (CPPS) and the glottal-to-noise excitation ratio (GNE) were shown to be highly valid, with a significant difference being demonstrated for each of the other perceptual voice quality aspects.

CONCLUSIONS

Two acoustic measures, the HNR and the PPQ5, were both strongly associated with perceptions of hoarseness and were able to discriminate hoarseness from breathiness with good confidence. Two other acoustic measures, the CPPS and the GNE, were both strongly associated with perceptions of breathiness and were able to discriminate breathiness from hoarseness with good confidence.

The maximum phonation time as marker for voice treatment efficacy: A network meta-analysis

PURPOSE

There is a diversity in treatment approaches for voice therapy in which aerodynamic treatment effects between the approaches are lacking. The evidence of voice treatments on the maximum phonation time (MPT) was quantified using the statistical approach of a network meta-analysis (NMA).

DATA SOURCES

Three databases and manual search from inception to November 2021 were evaluated.

STUDY SELECTION

Studies were considered which were reports of randomised controlled/clinical trials (RCT) evaluating the efficacy of a specific voice therapy treatment using MPT as an outcome measure in adult participants with voice disorders. Studies were excluded if participants had been diagnosed with neurological-motor-speech disorders or who were vocally healthy. Furthermore, no medical, pharmacological, or technical instrumental treatments were used.

DATA EXTRACTION AND SYNTHESIS

Preferred Reporting Items for systematic reviews and meta-analyses extension statement guidelines were followed. Two reviewers independently screened citations, extracted data, and assessed risk of bias using PEDro scale. Random effects model was used for meta-analysis.

RESULTS

We identified finally 12 RCT studies (treatment groups n = 285, and control group without an intervention n = 62). Eight interventions were evaluated. The only effective intervention with a significant effect was vocal function exercises (VFE) (mean pre-post difference 6.16 s, 95% confidence interval, 1.18-11.13 s).

CONCLUSIONS AND RELEVANCE

VFE effectively improved MPT from pre- to post-treatment in comparison with other voice interventions which were identified in the present NMA. Further high-quality intervention studies with large samples sizes, multidimensional measures, and homogeneous groups of dysphonia are needed to support evidence-based practice in laryngology.

Nutritional Biomarkers as Predictors of Dysphonia Severity in Patients with Ischemic Stroke

Dysphonia and malnutrition are major problems in patients who have suffered an ischemic stroke. Tools to assess dysphonia severity include the dysphonia severity index (DSI) and maximum phonation time (MPT). This study aimed to investigate whether the nutritional biomarkers transferrin, albumin, and prealbumin could be predictors of dysphonia severity. A retrospective analysis was conducted between January 2018 and October 2022. A total of 180 patients who had suffered an ischemic stroke were included. Serum transferrin, albumin, and prealbumin levels were significantly correlated with DSI and MPT levels. In a multiple regression analysis, prealbumin and transferrin were significant predictors of DSI, whereas only prealbumin was a significant predictor of MPT. Serum transferrin, albumin, and prealbumin levels in patients who have suffered an ischemic stroke may correlate with dysphonia severity as assessed using DSI and MPT. These results may provide objective evidence that nutritional biomarkers affect dysphonia severity.

Accuracy Analysis of the Multiparametric Acoustic Indices AVQI, ABI, and DSI for Speech-Language Pathologist Decision-Making

PURPOSE

To investigate the accuracy of the Acoustic Voice Quality Index (AVQI), the Acoustic Breathiness Index (ABI), and the Dysphonia Severity Index (DSI) for speech-language pathologist (SLP) decision-making in the evaluation of teachers' voice conditions.

METHODS

Cross-sectional observational study with a convenience sample composed of 21 teachers "fit" in carrying out their work activities as a teacher, and 21 considered "unfit" for the same. All teachers underwent a voice evaluation, carried out by a voice-specialized speech-language pathologist. Voice evaluation included the SLP's opinion on whether the teachers presented "fit" or "unfit" for work. The voice and speech samples used for the AVQI and ABI scores were the mid-three seconds of a sustained vowel /a/, and a spontaneous count from 1 to 10. The following parameters were used to extract the DSI score: mid-three seconds of a sustained vowel /a/, maximum phonation time of a sustained vowel /a/, ascending vocal glide on the vowel /a/ until reaching the highest pitch, and sustained vowel /a/ at the softest possible vocal intensity. The t-test was used to compare the difference between the AVQI and ABI indices. The Mann-Whitney test was used for the DSI index, with a confidence level of 95%. The receiver operating characteristic curve (ROC) was used for accuracy analysis.

RESULTS

There was a difference in AVQI values (P=0.008), ABI (P=0.014), and DSI (P=0.000) between groups. The cutoff points that revealed the highest specificity for the AVQI, ABI, and DSI respectively were 3.33 (sensitivity 57.1% and specificity 90.5%), 4 (sensitivity 57.1% and specificity 85.7%), and 1.62 (sensitivity 71.4% and specificity 90.5%).

CONCLUSION

The AVQI, ABI, and DSI are instruments that provide robust voice information and can help speech-language pathologists in their decision-making about whether teachers must or must not be restricted in their vocal activities at work.

Quantitative Measurement of Dysphonia Severity in Patients With Stroke With Unilateral Vocal Cord Palsy

Unilateral vocal cord palsy (UVCP) is frequently observed in patients with stroke. This study aimed to evaluate the association between objective dysphonia severity and the classification of UVCP in patients with stroke by objectively and quantitatively measuring their phonetic function. We recruited patients with UVCP diagnosed using laryngoscopy after stroke. Subgroups were divided according to UVCP type, and the dysphonia severity index (DSI) and maximum phonation time (MPT) were measured to objectively evaluate dysphonia. The DSI and MPT were compared between subgroups using analysis of variance with Tukey's honest significant difference post hoc test. In total, 103 patients with stroke and UVCP were recruited. We found that a higher UVCP severity possibly had to do with lower DSI and MPT values. We objectively confirmed that phonetic function was worse in patients with stroke with higher UVCP severity, and the DSI and MPT tests can be helpful in determining the severity and need for additional evaluation.