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

Effectiveness of Semi-Occluded Vocal Tract Exercises (SOVTEs) in Patients with Dysphonia: A Systematic Review and Meta-Analysis

BACKGROUND

Dysphonia is a disorder characterized by an alteration in the overall quality of the voice which reduces quality of life. Therefore, we assessed the effectiveness of SOVTEs in the management of dysfunctional and organic dysphonia for acoustic, perceptual-auditive, aerodynamic parameters and self-perception of the disease.

METHODS

a systematic review and meta-analysis were conducted. Findings were reported according to the PRISMA statement. Five databases were searched for RCTs and non- or quasi-RCTs. Studies were independently assessed using the Cochrane Risk of bias (RoB) and ROBINS-I tools. Effect sizes (ES) were calculated only at post-treatment. GRADE criteria were used to assess the quality of evidence.

RESULTS

eight articles were included. Studies investigated several SOVTEs, alone or in combination. None of the study was completely judged at low RoB. The quality of evidence resulted very low for each analysis. SOVTEs revealed to be statistically more effective than control interventions in improving F0 (ES: -14.42; CI 95%: -27.16, -1.69); P = 0.03), whereas shimmer did not change significantly (ES: -0.43; CI 95%:-02.02, 1.15; P = 0.59). Not significant changes in favor of control groups were found for jitter (ES: 0.13; CI 95%: -0.14, 0.40; P  = 0.34) and overall gravity in the perceptual-auditory evaluation (ES: 0.13 CI 95%: -0.50, 0.77; P = 0. 68). Among secondary outcomes, evidence suggested that SOVTEs are more effective than control interventions in Psub reduction (ES: -1.47; CI 95%: -2.84, -0.10; P = 0.03); self-assessment resulted not significantly in favor of SOVTEs (VHI/VRQoL: ES -0.23; CI 95% -1.14, 0.69; P = 0.63 and VTDS/VDSI: ES -4.85, CI 95% -25.13, 15.42; P = 0.64).

CONCLUSION

results obtained showed that voice therapy based on SOVTEs is not to consider significantly superior if compared to other treatments, even if a favorable trend was detected and should be taken into consideration. Further high-quality RCTs on specific SOVTEs are recommended to produce better-quality evidence.

High and Wide: An In Silico Investigation of Frequency, Intensity, and Vibrato Effects on Widely Applied Acoustic Voice Perturbation and Noise Measures

OBJECTIVES

This in silico study explored the effects of a wide range of fundamental frequency (fo), source-spectrum tilt (SST), and vibrato extent (VE) on commonly used frequency and amplitude perturbation and noise measures.

METHOD

Using 53 synthesized tones produced in Madde, the effects of stepwise increases in fo, intensity (modeled by decreasing SST), and VE on the PRAAT parameters jitter % (local), relative average perturbation (RAP) %, shimmer % (local), amplitude perturbation quotient 3 (APQ3) %, and harmonics-to-noise ratio (HNR) dB were investigated. A secondary experiment was conducted to determine whether any fo effects on jitter, RAP, shimmer, APQ3, and HNR were stable. A total of 10 sinewaves were synthesized in Sopran from 100 to 1000 Hz using formant frequencies for /a/, /i/, and /u/-like vowels, respectively. All effects were statistically assessed with Kendall's tau-b and partial correlation.

RESULTS

Increasing fo resulted in an overall increase in jitter, RAP, shimmer, and APQ3 values, respectively (P < 0.01). Oscillations of the data across the explored fo range were observed in all measurement outputs. In the Sopran tests, the oscillatory pattern seen in the Madde fo condition remained and showed differences between vowel conditions. Increasing intensity (decreasing SST) led to reduced pitch and amplitude perturbation and HNR (P < 0.05). Increasing VE led to lower HNR and an almost linear increase of all other measures (P < 0.05).

CONCLUSION

These novel data offer a controlled demonstration for the behavior of jitter (local) %, RAP %, shimmer (local) %, APQ3 %, and HNR (dB) when varying fo, SST, and VE in synthesized tones. Since humans will vary in all of these aspects in spoken language and vowel phonation, researchers should take potential resonance-harmonics type effects into account when comparing intersubject or preintervention and postintervention data using these measures.

Evidence on Vocal Interventions in Adults: A Scoping Review

OBJECTIVE

To map the evidence on vocal intervention in people over 18 years old.

METHODS

A literature search was conducted using the following electronic databases: Cochrane Library, EMBASE, Latin American and Caribbean Literature on Health Sciences (LILACS), LIVIVO, Pubmed/Medline, Scopus, SpeechBITE, and Web of Science. Gray literature was also used as an information source through searches on Google Scholar, Open Grey, ProQuest Dissertation and Thesis, and the Brazilian digital library of theses and dissertations. Systematic reviews (SR) with a population of individuals over 18 years old were included. The included reviews addressed speech-language pathology interventions in the vocal area with reports of their respective outcome. The methodological quality of the included systematic reviews was analyzed using the AMSTAR II tool. Quantitative analysis was performed by frequency distribution, and qualitative research was analyzed through narrative synthesis.

RESULTS

A total of 2,443 references were retrieved, among which 20 studies met the inclusion criteria. The included studies had critically low quality, lacking the use of population, intervention, comparison, and outcome (PICO) components. Among the included SRs, 40% were made in Brazil, 45% were published in the Journal of Voice, and 75% analyzed dysphonic patients. The most frequent intervention was voice therapy (direct therapy associated with indirect therapy approaches). Positive results were observed in most of the outcomes for all studies.

CONCLUSION

Voice therapy was described as inducing positive effects for voice rehabilitation. However, due to the critically low quality of studies, the literature did not enable us to understand the best results for each intervention. Well-designed studies are necessary to clarify the relationship between the intervention goal and how the intervention was evaluated.

A Meta-Analysis of the Association Between the Voice Handicap Index and Objective Voice Analysis

Purpose Dysphonia can be evaluated by both patient-reported quality of life instruments and objective acoustic and aerodynamic analyses. However, less is known about the association between the two metrics. The goal of this study was to perform a meta-analysis of the correlation of the Voice Handicap Index (VHI-30) with the following objective parameters: fundamental frequency, jitter, shimmer, harmonics to noise ratio, noise to harmonic ratio, maximum phonation time, and the Dysphonia Severity Index. Method A literature search was performed in the PubMed, Scopus, and Cumulative Index of Nursing and Allied Health Literature databases. Inclusion criteria were subjects age 18 years and older with voice complaints and assessed by both VHI-30 and objective voice analysis. Results A literature search resulted in 1,297 unique articles, of which 310 underwent full-text review and 17 studies were included in quantitative analysis. Significant pooled correlation was observed for VHI-30 total with jitter (.301 [.177; .416]), shimmer (.255 [.162; .344]), noise to harmonic ratio (.200 [.111; .285]), maximum phonation time (-.227 [-.352; -.094]), and Dysphonia Severity Index (-.254[-.455; -.0286]). Significant correlations were observed in 4/7 objective parameters with the Physical subscale, 3/7 with the Functional subscale, and 2/7 with the Emotional subscale. All significant correlations were negligible (0-.3) or low (.3-.5). Conclusions Results from meta-analysis showed that correlations between objective voice parameters and the VHI-30 were negligible or low. Further study is needed to determine if correlations vary by patient demographics or specific pathology.