Relations between Creaky Voice and Vocal Symptoms of Fatigue

Comprehensive Index of Vocal Fatigue (CIVF): Development and Clinical Validation

OBJECTIVES

In this study, we sought to investigate whether auditory-perceptual and acoustic measures change after a passage-reading task and to develop a multidimensional index of performance fatigue in voice disorders. The clinical usefulness and cut-off scores of the newly developed index were also explored.

METHODS

A total of 150 patients (age = 35.65 ± 11.44 years) with voice disorders and 100 healthy controls (age = 35.04 ± 11.26 years) were enrolled in the study. Overall severity (OS) and acoustic measures of sentence samples were obtained before and after a passage-reading task and compared between the two positions. Acoustic features included cepstral peak prominence (CPP), σCPP, L/H spectral ratio (SR), and σSR. Using the changes (Δ) in those acoustic measures and the scores of the Vocal Fatigue Index (VFI), a predictive model of the ΔOS was established. The clinical cut-off point of the index was also identified.

RESULTS

For the patient group, OS was higher, but CPP and σCPP were lower for the rear position (after reading the passage) compared to the front position (before reading the passage). A significant portion (adjusted R² = 77.7%) of the ΔOS was predicted by ΔCPP, tiredness score of the VFI, ΔσCPP, ΔσSR, and ΔSR. The area under the curve of the newly developed index was .864 (sensitivity, 78.67%; specificity, 78.00%), and the index's criterion was >2.6489.

CONCLUSIONS

The newly developed Comprehensive Index of Vocal Fatigue (CIVF) can quantify vocal fatigue in voice disorders, reflecting both acoustic and auditory perceptual changes after a passage-reading task. Further studies should explore the responsiveness of the CIVF and the impact of related factors on the CIVF in various voice disorders.

Does the Acoustic Voice Quality Index (AVQI) Correlate with Perceived Creak and Strain in Normophonic Young Adult Finnish Females?

BACKGROUND

The Acoustic Voice Quality Index (AVQI) is a correlate of dysphonia. It has been found to differentiate between dysphonic and normophonic speakers and to indicate the effects of voice therapy. This study investigates how the AVQI reacts towards creak and strain, which are common in normophonic speakers.

METHODS

The material was obtained from an earlier study on 104 Finnish female university students (mean age 24.3 years, SD 6.3 years) with no known pathology of voice or hearing and a perceptually normal voice (G = 0 in GRBAS), who were recorded while reading aloud a standard text and sustaining the vowel [a:]. Perceptual analysis for the amount of creak and strain was carried out by 2 expert listeners. In this study, the AVQI v03.01 was analyzed and correlated with perceptual evaluations. Samples with low and high amounts of creak and strain were compared with t tests.

RESULTS

On average, the AVQI was below the threshold value of dysphonia in the Finnish population. The AVQI (ρ = 0.35, p = 0.000) and its subparameters, smoothed cepstral peak prominence (CPPS; ρ = -0.35, p = 0.000) and harmonics-to-noise ratio (HNR; ρ = -0.30, p = 0.002) showed low but significant correlations with creak. Strain had low but significant correlations with spectral Slope (ρ = 0.38, p = 0.000) and Tilt (ρ = -0.40, p = 0.009). The AVQI was lower (better) in samples that were evaluated as having a high amount of strain, but the difference was not significant. Only CPPS differentiated significantly between low and high amounts of creak.

CONCLUSION

The AVQI does not seem to differentiate between high and low amounts of creak and strain in normophonic speakers.