Acoustic Voice Research Articles

Perceptual and acoustic voice analysis in patients with glottis cancer after endoscopic laser cordectomy.

<b>Introduction:</b> Treatment of glottis cancer, despite oncological safety, should consider postoperative voice quality. CO<sub>2</sub> laser endoscopic cordectomy allows radical removal of the tumor while maintaining respiratory, defensive and phonatory functions. <br><b>The aim:</b> The aim of the study is perceptual and acoustic evaluation of voice in patients after endoscopic CO2 III-Va laser cordectomy due to glottis cancer. <br><b>Material and method:</b> The study included 30 men after CO<sub>2</sub> cordectomy. 13 (43%) patients underwent type III cordectomy, 6 (20%) - type IV; 11 (37%) - type Va. Voice quality has been assessed 6 months after the surgery. Control group included 30 healthy men of the same age. GRBAS scale has been used in perceptual evaluation of voice. Acoustic analysis has been performed using DiagnoScope Specjalista software. Narrowband spectrography and Maximum Phonation Time (MPT) measure has been performed. <br><b>Results:</b> In study group, voice has been classified as G<sub>1</sub>R<sub>1</sub>B<sub>0</sub>A<sub>0</sub>S<sub>0</sub> after type III cordectomy; as G<sub>1</sub>R<sub>1</sub>B<sub>1</sub>A<sub>1</sub>S<sub>2</sub> in type IV and as G<sub>2</sub>R<sub>1</sub>B<sub>1</sub>A<sub>0</sub>S<sub>3</sub> in type Va. Acoustic evaluation revealed the highest values of F0, Jitter, Shimmer and NHR after Va cordectomy as well as non-harmonic components in narrowband spectrography and reduction of MPT. <br><b>Conclusions:</b> Postoperative voice quality depends on the type of cordectomy. Perceptual assessment indicates that type IV and Va cordectomy cause intensification of voice disorders. Parameters of acoustic evaluation increase with the extent of the procedure. The presence of non-harmonic components in narrowband spectrography increases with the extent of cordectomy, such as the reduction of MPT. Preservation of anterior commissure influences good voice quality in perceptual and acoustic assessment.

Analysis and Detection of Pathological Voice Using Glottal Source Features

Automatic detection of voice pathology enables objective assessment and earlier intervention for the diagnosis. This study provides a systematic analysis of glottal source features and investigates their effectiveness in voice pathology detection. Glottal source features are extracted using glottal flows estimated with the quasi-closed phase (QCP) glottal inverse filtering method, using approximate glottal source signals computed with the zero frequency filtering (ZFF) method, and using acoustic voice signals directly. In addition, we propose to derive mel-frequency cepstral coefficients (MFCCs) from the glottal source waveforms computed by QCP and ZFF to effectively capture the variations in glottal source spectra of pathological voice. Experiments were carried out using two databases, the Hospital Universitario Príncipe de Asturias (HUPA) database and the Saarbrücken Voice Disorders (SVD) database. Analysis of features revealed that the glottal source contains information that discriminates normal and pathological voice. Pathology detection experiments were carried out using support vector machine (SVM). From the detection experiments it was observed that the performance achieved with the studied glottal source features is comparable or better than that of conventional MFCCs and perceptual linear prediction (PLP) features. The best detection performance was achieved when the glottal source features were combined with the conventional MFCCs and PLP features, which indicates the complementary nature of the features.

Voice Characteristics in Patients with Acromegaly during Treatment

Active acromegaly is characterized by Growth Hormone and Insulin-like Growth Factor (IGF)-1 excess. Voice complaints are common in active acromegaly and are suggested to be caused by effects of Growth Hormone or IGF-1 on vocal folds and the surrounding soft tissues. Prospective studies on the course of voice characteristics in acromegaly patients are scarce and results are conflicting. This study investigates objective changes in voice parameters, self-reported perception of voice and laryngostroboscopic features during the first 2.5 years of acromegaly treatment. In this prospective study, acoustic voice analysis (and videolaryngostroboscopic examination were performed in 27 consecutive treatment-naive acromegaly patients at diagnosis (T0), after 1 year (T1) and after 2.5 years (T2) of treatment. The voice handicap index (VHI-30) questionnaire was taken. During acromegaly treatment, VHI scores decreased, and mucosal edema & hypertrophy diminished. No significant changes in objective voice parameters were detected. The within-subject change in serum IGF-1 levels (97.3 (40.6-208) to 22.4 (10.2-34.1) nmol/L (P < 0.001)) during follow-up correlated positively with the changes in VHI questionnaire scores (R 0.32-0.45; P=0.002-0.03). At diagnosis and during acromegaly treatment, mean VHI scores were in the normal range, although they decreased during follow-up. Mucosal edema and hypertrophy largely resolved during treatment. No significant changes in objective voice parameters were observed. Voice characteristics are in the normal range in patients with acromegaly, but may change during treatment. However, voice complaints are important to discuss, since they may influence quality of life.

Voice and Vocal Fold Condition Following Short-Term General Anesthesia: A Prospective Study

Dysphonia, with or without laryngeal changes, has been reported as a complication following prolonged intubation. In contrast, it is unknown if laryngeal changes also occur following short-term airway instrumentation. The objectives of this study were to determine the prevalence of laryngeal changes in patients undergoing short-term routine general anesthesia using an endotracheal tube (ETT) or supraglottic airway (SGA), and to identify predictors to these changes. Standardized voice assessments were performed preoperatively, postoperatively, and at follow-up on adults undergoing general anesthesia for an elective procedure of less than three hours requiring an ETT or a SGA. The standardized voice assessment protocol comprised a rigid videolaryngostroboscopy, the Voice Handicap Index (VHI), and acoustic voice analysis. The effects of demographic and anesthetic characteristics and type of airway instrumentation on the videolaryngostroboscopic variables were studied using multilevel logistic regression. Multilevel linear regression was used to reveal preoperative versus postoperative changes in VHI and acoustic voice scores. Overall, the prevalence of postoperative laryngeal changes was low. Significant postoperative laryngeal changes were found for the variables right-sided vocal fold redness in the ETT group (P=0.048) and right-sided vocal fold blood vessels in both groups (ETT versus SGA). However, after adjustment for all demographic and anesthetic characteristics in the regression model, the effect of the type of airway instrumentation (ETT versus SGA) on the variable right-sided vocal fold redness was no longer significant. ETT and SGA short-term airway instrumentation are vocal fold function sparing techniques with negligible laryngeal changes.

Voice of hearing impaired children and adolescents and hearing peers: influence of speech auditory perception on vocal production.

To compare the acoustic and perceptual-auditory results of the hearing impaired children and adolescents with hearing pairs and to correlate these results with parents' reports regarding speech auditory perception. The participants were divided into two groups: Group I, 20 hearing-impaired children and adolescents and Group II, 20 children and adolescents with normal hearing. Acoustic analysis of the vowel /a/ and perceptual-auditory assessment of the vowel /a/ and speech were performed. The speech auditory perception of the GI was assessed using the Infant-Toddler Meaningful Auditory Integration Scale and the Meaningful Auditory Integration Scale with adaptation for adolescent participants. The acoustic and perceptual-auditory voice results of the GI and GII were compared and these results were correlated with the performance in the auditory perception of the GI group. The groups I and II presented similar results, differing statistically in the long-term frequency variation (vF0) and the long-term amplitude variation (vAm) parameters of the vowel /a/ and speech resonance parameter. It was found a negative correlation between auditory perception performance with jitter, vF0 and general degree of vowel /a/. The vocal quality in GI was similar to their hearing peers in almost all the vocal parameters that were analyzed. The auditory perception influenced jitter, vF0 and general degree of voice parameters, in which hearing-impaired children and adolescents who presented higher scores for auditory perception were also able to keep a more controlled vocal emission.

Laryngostroboscopy and voice evaluation in adult patients with Parkinson s disease

Introduction: Most patients with Parkinson’s disease (PD) present tongue, larynx and pharynx disorders, affecting voice and speech. Objective: To evaluate the laryngeal manifestations of PD. Methods: Evaluation of 18 PD patients conducted between January 2011 and December 2012. Patients were evaluated through videolaryngostroboscopy, auditory perceptual analysis of the voice using the GIRBAS scale, acoustic voice analysis, and application of the Vocal Handicap Index (VHI) questionnaire. Results: Dysphonia and vocal fatigue were referred by 72.22 and 33.3% of the patients, respectively, whereas changes during laryngoscopy were verified in 94.44%. The medians of the acoustic voice analysis and the VHI self-assessment questionnaire were unchanged. The median of the VHI emotional domain was higher among patients who presented open phase closure, with statistically significant difference (p=0.029). Conclusion: Patients with PD present laryngeal and voice changes.

Evaluation of the Relationship Between the Required Pressure Level in Continuous Positive Airway Pressure Treatment and Voice in Patients With Obstructive Sleep Apnea Syndrome

The aim of this study was to investigate the effect of obstructive sleep apnea syndrome on voice, the relationship between the required pressure levels in continuous positive airway pressure (CPAP) and voice, and the effects of CPAP therapy on voice. A total of 73 subjects consisting of 53 patients and 20 control subjects were included in the study. The patient group was further divided into low- (Group A) and high- (Group B) pressure groups according to the required pressure level. All subjects underwent acoustic sound analysis to evaluate fundamental frequency (F0), jitter, shimmer, and noise-to-harmonics ratio (NHR). Acoustic voice analysis was repeated after 3 months of regular CPAP treatment in the patient group. The mean F0, jitter, shimmer, and NHR values of the patient group and control group were compared. Intergroup comparisons were also performed between Group A and the control group, and between Group B and the control group. Finally, before and after CPAP treatment values of mean F0, jitter, shimmer, and NHR were compared in Group A and Group B. The mean shimmer and NHR values of the patient group were significantly higher than the control group (P=0.01 and P=0.023, respectively). The mean shimmer and NHR values of Group B were statistically higher than the control group (P=0.002 and P < 0.001, respectively). The mean jitter, shimmer, and NHR values after CPAP treatment were significantly lower than those measured before CPAP treatment in Group B (P=0.003, P=0.001, and P=0.001, respectively). Voice is negatively affected in obstructive sleep apnea syndrome patients who require high pressure in CPAP treatment. CPAP treatment leads to improved voice in these patients.

Long-Term Effects of a Voice Training Program for Teachers on Vocal and Mental Health

The voice is an important occupational tool for teachers. Voice training programs have been shown to help strengthen the voice health and endurance. However, longitudinal studies on voice trainings are sparse. In this study, long-term effects nearly 2 years after a voice training program have been investigated. The acoustic voice quality (Dysphonia Severity Index [DSI]), the voice self-concept (Fragebogen zur Erfassung des Stimmlichen Selbstkonzepts), and the health-related quality of life (SF-12) of 55 teachers who participated in a prior voice training program of ten 90 minutes sessions were compared to 33 teachers without voice training. The participants were measured at three times: in a pre- and a post-training survey and in a 2-years follow-up survey. The trained teachers increased in DSI over all three surveys while the nontrained teachers decreased in DSI with a significant interaction effect. Also the trained teachers significantly increased the awareness of voice use and their mental health compared to the nontrained group. The positive effects of the voice training, which have been found between pre- and post-training and in comparison with the control group, clearly sustained in long-term 2 years after the end of the training. This finding emphasizes the importance of voice training for teachers as a long-term investment for a voice-related healthy working life.

Effects of Vocal Intensity and Fundamental Frequency on Cepstral Peak Prominence in Patients with Voice Disorders and Vocally Healthy Controls

Cepstrum-based voice measures, such as smoothed cepstral peak prominence (CPPS), are influenced by voice sound pressure level (SPL) in vocally healthy adults. Since it is unclear if similar effects hold in voice disordered adults and how these interact with natural fundamental frequency (fo) changes, this study examines voice SPL and fo effects on CPPS in women with vocal hyperfunction and vocally healthy controls. Retrospective matched case-control study. Fifty-eight women with vocal hyperfunction were individually matched with 58 vocally healthy women for occupation and approximate age. The patient group comprised women exhibiting phonotraumatic vocal hyperfunction associated with vocal fold nodules (n=39) or polyps (n=5), and nonphonotraumatic vocal hyperfunction associated with primary muscle tension dysphonia (n=14). All participants sustained the vowel /a/ at soft, comfortable, and loud loudness conditions. Voice SPL, fo, and CPPS (dB) were computed from acoustic voice recordings using Praat. The effects of loudness condition, measured voice SPL, and fo on CPPS were assessed with linear mixed models. Pairwise correlations among voice SPL, fo, and CPPS were assessed using multiple regression analysis. Increasing voice SPL correlated significantly (P < 0.001) with higher CPPS in both patient (r2=0.53) and normative groups (r2=0.45). fo had statistically significant effects on CPPS (P < 0.001), but with a weak relation for the patient (r2=0.02) and control groups (r2=0.05). In women with and without voice disorder, CPPS is highly affected by the individual's voice SPL in vowel phonation. Future studies could investigate how these effects should be controlled for to improve the diagnostic value of acoustic-based cepstral measures.

Effects of thyroplasty implant stiffness on glottal shape and voice acoustics.

ObjectivesVocal fold (VF) stiffness and geometry are determinant variables in voice production. Type 1 medialization thyroplasty (MT), the primary surgical treatment for glottic insufficiency, changes both of these variables. Understanding the cause and effect relationship between these variables and acoustic output might improve voice outcomes after MT. In this study, the effects of thyroplasty implants with variable stiffness on glottal shape and acoustics were investigated.MethodsIn an ex vivo human larynx phonation model, bilateral MT with implants of four stiffness levels (1386, 21.6, 9.3, and 5.5 kPa) were performed. Resulting acoustics and aerodynamics were measured across multiple airflow levels. A vertical partial hemilaryngectomy was performed and stereoscopic images of the VF medial surface taken to reconstruct its three‐dimensional (3D) surface contour. The results were compared across implants.ResultsThe effects of implant stiffness on acoustics varied by airflow. Softer implants resulted in improved acoustics, as measured by cepstral peak prominence (CPP), at lower airflow levels compared to stiffer implants but this relationship reversed at high airflow levels. Stiffer implants generally required less airflow to generate a given subglottal pressure. Stiffer implants resulted in greater medialized surface area and maximal medialization, but all implants had similar effects on overall VF medial surface contour.ConclusionSofter implants result in less medialization but better acoustics at low airflow rates. Stiffer implants provide better acoustics and more stable pressure‐flow relationships at higher airflow rates. This highlights a potential role for patient‐specific customized thyroplasty implants of various stiffness levels.Level of EvidenceNA.

Automated ambient recognition method based on dynamic center mirror local binary pattern: DCMLBP

Voice recognition and sound classification is a hot-topic research area in the literature and many methods have been presented. Ambient recognition is very important problem by using voices or acoustic. Especially, digital forensics examiners need an automated ambient recognition system by using acoustical voices. In this study, a novel automatic ambient recognition method is presented by using acoustic. Firstly, an acoustical voice dataset is acquired. These voices are categorized in the 8 classes and these classes are kinder garden, ferryboat, airport, café, subway, bus, traffic and walking. Then, a sequential learning method is presented for ambient recognition using acoustical voices. The proposed method consists of dynamic center mirror local binary pattern (DCMLBP) and discrete wavelet transform (DWT), neighborhood component analysis (NCA) based feature selection and classification phases. By using DWT, a sequential learning method is proposed and the proposed feature extraction method has nine levels. Experiments clearly show that the proposed DCMLBP based method has high classification accuracy, precision, geometric mean, F-score for ambient recognition. According to results, the best accuracy rate was calculated as 99.97% ± 0.07% by using support vector machine and 128 features.

The Usefulness of Auditory Perceptual Assessment and Acoustic Analysis as a Screening Test for Voice Problems

Background/Aims: The aims of study were (1) to determine the cut-off values of parameters related to auditory perceptual assessment (visual analog scale [VAS]) and acoustic analysis (cepstral peak prominence [CPP], low-frequency/high-frequency [L/H] ratio, CPP SD, L/H ratio SD, acoustic voice quality index [AVQI], and cepstral spectral index of dysphonia [CSID]) for predicting voice problems within a Korean population, and (2) to verify the discriminative power of these cut-off values. Methods: 1,113 voice samples were analyzed in this study. Perceptual assessments (VAS) were performed by 5 speech-language pathologists. For the acoustic analysis, cepstral parameters, CSID, and AVQI were calculated. The cut-off values of parameters predicting voice problems were obtained using receiver operating characteristic (ROC) analysis. Additionally, the sensitivity, specificity, and area under the ROC curve (AUC) were measured. Results: High reliabilities were observed for the perceptual assessments. The cut-off values of parameters had a high sensitivity, specificity, and AUC. Of these, CSID was the parameter with the highest AUC values. Conclusion: Each parameter demonstrated a high discriminative power for classifying the presence or absence of voice problems. The results of this study could be used as an objective criterion for screening voice problems.

Diagnostic Value of Acoustic and Aerodynamic Measurements in Vocal Fold Movement Disorders and their Correlation with Laryngeal Electromyography and Voice Handicap Index

Investigate the relationships between the Voice Handicap Index, laryngeal electromyography, and objective acoustic voice testing in order to determine the utility of these measures in the management of vocal fold movement disorders. A retrospective review of patients who had completed a Voice Handicap Index-10 (VHI-10) questionnaire, laryngeal electromyography (LEMG), and objective acoustic measurements (including jitter, relative average perturbation, shimmer, noise-to-harmonic ratio, and standard deviation of fundamental frequency). All three tests had been completed within 30 days of the initial evaluation. All patients' results for acoustic measures were recorded as standard deviations from the norm. LEMG results were converted to grade of paresis (mild, moderate, severe) based on the muscle with the lowest recruitment. Spearman correlation coefficients were calculated to determine the relationship between these three parameters. A total of 313 subjects were included in the analysis. VHI-10, LEMG (grade of paresis), and objective acoustic measures were, at best, weakly correlated. VHI-10 was better correlated than LEMG to each acoustic parameter including the average acoustic scores; however, the highest correlation observed only reached ρ = 0.349 (P < 0.001). The acoustic variables that correlated best with VHI-10 and LEMG were the standard deviation of the fundamental frequency (ρ = 0.349, P < 0.001) and shimmer (ρ = 0.207, P < 0.001), respectively. This study demonstrates that these measures are, at best, weakly associated. VHI-10 correlated better than LEMG (grade of paresis) to each acoustic voice analysis parameter. However, the maximum correlation coefficient observed was 0.349. Therefore, VHI-10 scores and objective voice acoustic measurements are not useful for predicting the severity of vocal fold movement disorders. Moreover, a given severity of paresis can have different effects on voice handicap and acoustic output in different individuals.

Treatment Outcomes of Arytenoid Dislocation by Closed Reduction: A Multidimensional Evaluation

This study aimed to investigate the treatment outcomes of arytenoid dislocation by a multidimensional evaluation. From April 2010 to May 2018, the records of 57 patients with a history of arytenoid dislocation were reviewed. All the patients were treated with closed reduction under local anesthesia. Arytenoid motion, grade, roughness, breathiness, asthenia, strain, maximum phonation time, self-assessed Voice Handicap Index, and acoustic voice analysis were used to evaluate the clinical outcomes. Following closed reduction, 57 patients were divided into "recovered" (n = 24), "improved" (n = 15), and "ineffective" (n = 18) groups. There were no major complications resulting from surgical intervention. Closed reduction under local anesthesia continues to be an effective and well-tolerated method for treating arytenoid dislocation. The trichotomy of the treatment results of arytenoid dislocation by a multidimensional evaluation may be more accurate to evaluate the results of arytenoid dislocation.

Validation of Acoustic Voice Quality Index Version 3.01 and Acoustic Breathiness Index in Korean Population

This study aimed to verify the Acoustic Voice Quality Index (AVQI) version 3.01 and the Acoustic Breathiness Index (ABI) as tools for acoustic analyses in the Korean language. Concatenated voice samples of sustained vowels (SV) and continuous speech (CS) were collected from 151 subjects with dysphonia and 71 vocally healthy subjects. The overall voice disorder severity (grade [G] and overall severity [OS]) and breathiness severity (B) were subjected to an auditory-perceptual rating by three raters. First, we equalized the proportions of SV and CS with respect to the time lengths of the voice samples to improve the ecological validity. We then validated the AVQI and ABI in the Korean language, using our most recent dataset of 1,667 voice samples. Second, we compared the results of the acoustic analyses between the vocally healthy controls and the dysphonia groups. Third, we confirmed the concurrent validity and diagnostic accuracy using the Spearman rank-order correlation coefficient (rs) and various statistical methods (receiver operating characteristic curve, pairwise comparison, and likelihood ratio [LR] analyses). We observed strong inter-rater reliability for G, B, and OS. Moreover, we identified 26 standardized syllables in the CS samples (3 second voiced segments), which allowed the equalization of both voice tasks. A comparison of the two voice groups revealed statistically significant differences in the AVQI, ABI, G, B, and OS (all P < 0.01). Moreover, we identified strong correlations of the AVQI with G (rs > 0.88, P < 0.01) and OS (rs > 0.84, P < 0.01) and of ABI with B (rs > 0.87, P < 0.01). Finally, we confirmed cutoffs of 3.154 (sensitivity: 90%, specificity: 89%, LR+: 8.45, and LR-: 0.12) and 3.685 (sensitivity: 88%, specificity: 86%, LR+: 6.47, and LR-: 0.14) as optimal predictive powers for AVQI and ABI, respectively. As per our results, in a sample of Korean speakers, the AVQI and ABI exhibited strong concurrent validity for the quantification of dysphonia severity with respect to OS and B. We consider that analyses based on the AVQI and ABI will enable the discrimination and assessment of dysphonia in clinical practice.

Objective and Subjective Evaluations of the Effects of Different Types of Intubation Tube Applications on Voice Performance in the Early Postoperative Period.

ObjectiveChanges in voice performance in the postoperative period due to trauma suffered during endotracheal intubation or edema occurring in the postoperative period are often observed. The present study aimed to evaluate the effects of different types of intubation tube applications on voice performance in the early postoperative period using objective and subjective voice analysis methods.Materials and MethodsA total of 88 patients who underwent endotracheal intubation either using a cuffed endotracheal (n = 44) or spiral-embedded cuffed endotracheal (n = 44) tube were included in this study. An endotracheal tube of 7.5 mm was used for female patients and that of 8 mm was used for male patients. Preoperative acoustic voice analysis was performed, and fundamental frequency (F0), jitter%, and shimmer% values were recorded. In addition, the voice handicap index-30 (VHI-30) questionnaire was completed by the patients for subjective evaluation. The same procedure was repeated in the first 48 hours postoperatively. The preoperative and postoperative data were statistically compared. In addition, the effect of the type of endotracheal intubation tube on acoustic voice analysis parameters and VHI-30 scores was statistically evaluated.ResultsIn the early postoperative period, a significant decrease in the F0 value and a significant increase in jitter% and shimmer% values were detected. The VHI-30 score was also found to be significantly higher in the early postoperative period than in the preoperative period. The effects of both the intubation tubes on voice performance were found to be similar.ConclusionObjective and subjective evaluations revealed that voice performance was declined in the early postoperative period after orotracheal intubation.

Estimation of vocal fold geometry and stiffness from voice acoustics

Many speech applications require estimating vocal fold properties from the produced acoustics. While there have been many previous research on solving the inverse problem, they are often based on lumped-element models of phonation, whose model parameters are difficult to relate to realistic vocal fold properties. This study explores the feasibility of inferring physiologically realistic vocal fold properties, including vocal fold length, thickness, depth, anisotropic stiffness moduli, and the subglottal pressure, from the produced acoustics, using a three-dimensional phonation model and a Bayesian inference approach. To reduce the computational cost associated with the use of a three-dimensional model and the large number of inputs to be estimated, we explore the possibility of improving computational efficiency and estimation accuracy using the large amount of three-dimensional simulation data available from our previous research. Preliminary results show that joint likelihood probabilities can be reasonably estimated based on the available simulation data, significantly reducing computational costs of Bayesian inference. The approach is able to estimate the control parameters of voice production from the produced acoustics with reasonable accuracy. It is observed that certain control parameters, particularly vocal fold stiffness, consistently have large estimation errors than others. [Work supported by NIH.]

Within- and between-speaker acoustic variability: Spontaneous versus read speech

Using principal component analysis (PCA), our previous study [JASA 145(pt. 2), 1930, (2019)] of read sentences found surprisingly similar acoustic voice spaces for groups of female and male talkers and for the individuals within groups. Formant frequencies and the balance between higher harmonic amplitudes and inharmonic energy in the voice accounted for the most acoustic variance within and across talkers, but many further details varied idiosyncratically for individual talkers. In this study, we replicated this finding using a set of recorded phone conversations from 99/100 original speakers (49 F), hypothesizing that the same measures would characterize both individual and population acoustic spaces, despite greater acoustic variability for spontaneous utterances. F0, formant frequencies, spectral noise, source spectral shape, and their variability were measured every 5 ms from vowels and approximants. Individual and group PCAs revealed that the acoustic voice spaces derived from spontaneous speech are highly similar to those spaces previously identified based on read speech. One significant difference between the two speaking styles was that unlike read speech, variability in F0 emerged as one of the variables that accounted for significant acoustic variability in spontaneous speech. Implications for voice learning, recognition, and discrimination will be discussed. [Work supported by NIH/NSF.]

GALP Qualifier Scale: Initial Considerations to Classify a Voice Problem

Objective: To propose a single qualifier scale for voice problems based on the International Classification of Functioning, Disability, and Health (ICF) that classifies a voice problem considering its multidimensionality. Method: A multicultural database was analyzed (280 subjects). The analyzed information was: the perceptual judgment of the overall voice quality (G); the acoustic analysis (A) with the Acoustic Voice Quality Index; the laryngeal diagnosis (L) and the patient self-assessment (P) using the Voice Handicap Index. The variables were categorized. A 2-step cluster analysis was performed to define groups with common characteristics. Results: A 7-point qualifier scale, the GALP, was defined to generally classify levels of voice problems considering 4 dimensions of the voice evaluation. Each level of voice problem, that is, no problem, mild, moderate, severe, or complete voice problem, has its own possible outcome for G, A, L, and P that will change, or not, the overall level of voice problem. The extremes of the scale represent “no problem” at all when all parameters are normal, and “complete problem” when all parameters are altered. The 3 levels in between were defined by the cluster analysis (mild, moderate, and severe problem) and change according to the outcome of each evaluation (G, A, L, and P). Thus, changes in one parameter alone may or not contribute to the change of the level of voice problem. Also, there are 2 categories for cases that do not fit the classification (not specified) and for which some of the variables are missing (not applicable). Conclusion: The GALP scale was proposed to classify the level of voice problem. This approach considers important dimensions of voice evaluation according to the ICF. It is a potential tool to be used by different professionals, with different assessment procedures, and among different populations, clinicians, and study centers.

Acoustic Voice Quality Index as a Potential Tool for Voice Screening

To diminish the risk of voice disorders in people who are highly dependent on their voices, such as teachers, vocal screening is important already at the beginning of such individuals' professional studies. A reliable, specified screening tool is needed. The Acoustic Voice Quality Index (AVQI) has been found to differentiate normal voices from abnormal voices and to serve as a treatment outcome measure. This study investigated whether AVQI could be a screening tool in combination with auditory- and self-perception of the voice to discriminate normal from slightly poor voices. Experimental. Some 128 female teaching students (mean age 26.39 years, SD 9.80 years) with no diagnosed voice disorders participated in this study. They read aloud a text in Finnish, sustained the vowel /a:/, and filled the Voice Handicap Index (VHI) questionnaire. Voice samples were recorded with an AKG C544L headset microphone, iFocusrite soundcard, and Praat software using a 44100 sample rate and 16-bit amplitude quantization. Five expert voice therapists evaluated the samples to determine the grade of dysphonia (G) using a scale of 0-0.5 (=normal), 0.5-1 (=mild), 1-2 (=moderate), and 2-3 (=severe). Three medial seconds of [a:] and the first 31 syllables of the text were analyzed using AVQI script version 03.01 in Praat (5.3.55). The analysis gives one AVQI score per participant (scale 0-10). The AVQI threshold of normal and disordered voices for Finnish speakers is 1.83; a Gmean = 0.0-0.5 and VHI score <19 were considered normal. Statistical analysis was done using the receiver operating characteristic (ROC) curve, Spearman's correlation coefficient, and the independent samples t test. According to the AVQI results, the area under the curve (AROC) was 0.554, which is fair. The Youden index gave a cutoff value of 0.30 with a sensitivity of 85% and a specificity of 81.1%. There were weak but significant correlations between Gmean and AVQI and two AVQI parameters, smoothed cepstral peak prominence and harmonic-to-noise ratio (r = 0.27; --0.24; -0.20, respectively; |P < 0.05); and between total VHI and AVQI score and cepstral peak prominence (r = 0.21; 0.20, respectively; P < 0.05). Furthermore, the AVQI scores differed significantly between the groups with a VHI total score <19 and ≥19. AVQI did not differentiate between voices that had been perceptually judged as normal or slightly abnormal, but a combination of perceptual assessment in the form of AVQI and VHI could better screen slightly deviant voices.