Download pdf - Creating a Mastery Experience During the Voice Evaluation

Creating a Mastery Experience During

the Voice Evaluation

Heather Shaw Bonilha and Amy Elizabeth Dawson, Charleston, South Carolina

Summary: Objectives. Adherence to treatment is a common challenge when working with patients with voice dis-

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orders. Improving their self-efficacy through a mastery experience has the potential to improve treatment adherence. Anideal mastery experience gives early and quick evidence that the patient will be successful with the treatment and worksfor a broad range of patients. This study sought to test whether a brief stimulability trial of forward focused voice couldproduce sufficient change in acoustic analysis measures to provide visibly improved objective results and, thus, bea potentially useful mastery experience.Study Design. Prospective, repeated measures, pre- and posttreatment.Methods. Twenty-four consecutive patients with varying diagnoses referred for a voice evaluation participated in thisstudy. Acoustic analysis was completed before and after a short stimulability trial of forward focused voice. Acousticanalysis parameters evaluated include fundamental frequency, jitter, shimmer, noise-to-harmonic ratio, and voice tur-bulence index. Data pre- and posttreatment were analyzed for change and compared with normative values.Results. Results demonstrated a significant change from pre- to posttrial, as indicated by the objective measure tran-sitioning from being outside to within normal limits, in 75% of patients (P¼ 0.000). When less rigid criterion of a pos-itive change in one or more of the three acoustic measures of interest is used, improvement was noted in 96% of patients.Conclusion. Pairing a trial therapy with acoustic analysis during a voice evaluation is a possible mastery experience.Future research is needed to determine if this mastery experience improves self-efficacy, treatment adherence, and treat-ment outcomes.Key Words: Voice–Evaluation–Mastery experience–Self-efficacy–Acoustic analysis.

INTRODUCTION

A common difficulty experienced by clinicians is engagingtheir patients in treatment. Most treatment typically involveshealth behavior changes. This is especially true for patientswho require voice treatment. For successful health behaviorchanges, a patient must have sufficient self-efficacy andmotiva-tion to engage in and continue voice therapy. It is documentedthat many patients with voice disorders do not adhere to ther-apy.1,2 In 2006, Portone et al in a retrospective review of 294charts found that 47% of patients who were seen for a voiceevaluation adhered to the recommendation of a speech-language pathologist (SLP) for voice therapy. In a follow-upstudy, Hapner et al found that 65% of patients dropped out ofvoice therapy. Patient demographics, quality-of-life impact, se-verity of dysphonia (consensus auditory perceptual evaluationof voice), and diagnosis (hyperfunctional vs hypofunctional)were not predictive of patient dropout. It is possible that thislack of adherence is related to the inherent difficulty in makinghealth behavior changes.

The transtheoretical model (TTM) describes health behaviorchange as a process that progresses in a series of stages.3 Tomake and maintain a health behavior change, one must progressthrough all stages successfully. The TTM has been studied and

ted for publication September 15, 2011.s of this study were presented at the 39th Symposium of The Voice Foundation:e Professional Voice; June 2010; Philadelphia, Pennsylvania, and the Pan Europeannference; September 2011; Marseille, France.the Department of Health Science and Research, Medical University of South, Charleston, South Carolina.ss correspondence and reprint requests to Heather Shaw Bonilha, Department ofcience and Research, Medical University of South Carolina, 77 President Street,n, SC 29425. E-mail: [email protected] of Voice, Vol. 26, No. 5, pp. 665.e1-665.e7997/$36.002 The Voice Foundation.1016/j.jvoice.2011.09.004

used as a behavior change assessment technique for a number ofhealth concerns. Researchers have determined the TTM to beeffective and useful for physical activity exercise, alcohol con-sumption, and smoking cessation.4,5

There are five stages of change described in the TTM. Pre-contemplation, the first stage, occurs when a patient is not yetconsidering behavioral therapy. This can be attributed to thepatient being unaware that a problem behavior needs to bechanged or that a change would be beneficial. Congruently,they could be aware of a possible change but are unwilling topursue it. It is also thought that general indecision may playa role in the precontemplation stage. That is, a patient may beaware that a behavior change is possible, but he or she is stillweighing the pros and cons of making that change.6–8 The con-templation stage occurs when a patient is in fact starting to con-sider making a behavior change, but he or she has yet to act onthe thought. The preparation stage is characterized by a patient’sresolve to pursue change. The action and maintenance stagesare regarded as the period when a person takes steps to modifyhis or her behavior and prevent relapse or recycling into previ-ous stages.6,7

Important to the TTM is the concept of self-efficacy or an in-dividual’s confidence in his or her ability to accomplish a task.9

Self-efficacy is necessary to achieve and maintain behaviorchange, and, fortunately, it is changeable within an individual.9

A commonly observed characteristic in patients with higherself-efficacy is that they have a better prognosis. The socialcognitive theory proposes and has accrued evidence for foursources of self-efficacy: mastery experience, vicarious experi-ence, verbal persuasion, and emotional-physiological state.6,10

Cognitive structures, such as self-efficacy, are most success-fully reformed by a personal mastery experience arising froman effective accomplishment or productive behavior.9 In order

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Journal of Voice, Vol. 26, No. 5, 2012665.e2

for a mastery experience to be successful in improving patients’confidence in therapy, it must be easily interpretable by patientsas presenting an improvement and prove advantageous for mostpatients.

For patients with voice disorders, the first opportunity at pro-viding amastery experience is in the initial evaluation with stim-ulability trials. A patient’s presence or absence of stimulabilityfor therapy must be assessed to determine an appropriate treat-ment plan. The stimulability trial can also be used to determinewhether or not a patient believes that a certain treatment has thepotential to relieve their symptoms. This time point generally re-lates to the precontemplation or contemplation stages of theTTM, making it an ideal time to increase a patient’s self-efficacy. Patients may be in the precontemplation stage at thevoice evaluation because, although they have been referred toan SLP, theymay not yet know the extent towhich their behaviorneeds changing or that a change would even be beneficial. Pa-tients are in the process of learning about their behavior andits negative impacts on the voice and weighing the pros andcons to modifying the behavior. Once they are knowledgeableabout their condition and the health behavior changes suggestedby the SLP, they maymove onto the contemplation stage. This iswhen the patients are not yet resolved to engage in therapy or putin the effort required to modify their behavior, and/or, they arenot yet convinced that the therapy the SLP has to offer will, infact, prove beneficial. The patients are actively acquiring infor-mation about their condition at this point, acknowledging thatthey have a problem, and investigating their treatment options.Patients may present to the voice evaluation in either the precon-templation or the contemplation stage. When patients move tothe contemplation stage, they are actively seeking evidence sup-porting the efficacy of voice therapy; therefore, patients in thisstage are prone to benefit from cognitive methodologies usedto increase motivation.8 The use of the treatment stimulabilitytechnique proposed in this article may be helpful in movingpatients from the precontemplation and contemplation stagesto the preparation, action, and maintenance stages and inpreventing reversion into the previous stages.

Before evaluating the outcome of a mastery experience forimproving a patient’s self-efficacy, adherence to therapy, orvoice quality, we needed to develop a viable mastery experiencerelevant to most patients. The first step was to identify a voicetherapy approach to use for the stimulability trial that wouldbenefit and not harm the largest number of patients whilequickly providing notable voice improvement. Based on typicalpractice patterns and the author’s clinical biases, a forwardfocused (resonant) voice approach was chosen for this study.This approach was chosen based on the concept that bothpatients with hyperfunctional and hypofunctional voice disor-ders benefit from forward focused voice therapy. Althoughforward focused voice is predominately touted for its position-ing of the vocal folds during phonation to minimize forcefulcontact and presumably allow tissue healing, it is also usefulfor persons with hypofunctional voice disorders for the samereason.11 Because forward focused voice does not require thesame level of vocal fold contact as nonforward focused phona-tion to be produced, it works with the anatomy of patients with

hypofunctional voice disorders to also improve their voicequality. Additionally, there is a relatively low possibility ofharming the vocal fold tissue during a supervised trial of for-ward focused therapy during the voice evaluation. As reportedby Boone and McFarlane,12 the approach is generally helpful topatients with voice disorders with the exception of those whosedisorder involves a hypernasality component. Forward focusedvoice has the advantage of providing a large amount of innatefeedback to the patient. Forward focused voice exercises pro-vide the feeling of vibration or sensation on the lips or in themouth, a decrease in laryngeal tension, and an immediatechange in voice quality. Forward focused voice exercises areubiquitous in the voice clinic and have been part of many voicetherapy approaches advocated by the leaders in the field.13–15

Other voice therapy approaches that may provide similarlyfast changes in vocal quality may also be appropriate for thispurpose depending on the individual patient characteristics.A noninclusive list of such therapies that may be explored forthis purpose are the Lessac-Madsen resonant voice therapy,vocal function exercises, the accent method, flow phonation,and the Lee Silverman voice treatment.The second step in formulating the mastery experiencewas to

identify the appropriatemeasure of success that would be readilyadopted by the patient. We chose acoustic analysis for this pur-pose because it is both a biofeedback and a measurement tech-nique that provides a clear means for the patients tounderstand that they are improving. Because of the objective na-ture, visual display, and ability to replay the phonation, acousticanalysis seemed to provide the most opportunity for relaying in-formation on the change from the prestimulability to poststimul-ability trial. Anecdotally, information from acoustic analysis,both the visual image of the red and green diagram from multi-dimensional voice program (MDVP) and the numerical results,seems to be a measure that naturally resonates with patients.

PURPOSE

The purpose of this study was to evaluate whether objectiveacoustic analysis paired with a short stimulability trial of for-ward focused voice provides positive feedback to most patients.If acoustic analysis during a forward focused stimulability trialprovides early, quick, and positive feedback for most patients, itmay be a useful mastery experience to improve patient adher-ence to and benefit from voice therapy. The long-term planfor this line of research is to follow patients who are exposedto this mastery experience to determine if this approach doesimprove self-efficacy, treatment adherence, and behavioraltreatment outcomes.The specific research questions for the first step in this pro-

cess were

1. Do the acoustic analysis parameters of frequency and am-plitude perturbation, noise-to-harmonic ratio (NHR), andvoice turbulence index (VTI) differ before and after voicestimulability trials?

2. Is the change of fundamental frequency (Fo), not thechange in voice quality because of the treatment,

Heather Shaw Bonilha and Amy Elizabeth Dawson Mastery Experience 665.e3

responsible for the changes in acoustic analysis measuresbetween pre- and poststimulability trial recordings?

FIGURE 1. Box plot of RAP during the four tasks: pretask habitual

pitch, pretask high pitch, pretask low pitch, and posttask habitual pitch.

METHOD

Participants

Twenty-four consecutive patients referred for voice evaluationat the Medical College of Georgia (MCG) participated in thisstudy. The procedures used in this study were those commonlyused for the evaluation of patients with voice disorders. Thedata for this study were assessed in a retrospective chart reviewapproved by the institutional review board of the MCG. The pa-tients included in this study were not restricted by any criteria.The patients referred had diagnoses ranging from prenodules topresurgery for cysts to unilateral paralysis.

Data collection

Participants were recorded sustaining /a/ at habitual pitch andvolume, high pitch and habitual volume, and low pitch and ha-bitual volume with a headset microphone. Subjects were notguided in the selection of pitch for any of the tasks. Patientsthen underwent a stimulability trial that ranged from 3 to 5 min-utes. The trial duration depended on the patient’s ease of learn-ing the task. The stimulability trial began by asking the patientsto take a breath and hum; they were then asked to repeat this andfeel for any vibration or sensation on their lips or the front oftheir mouth. Patients who were instructed to specifically attendto their oral cavity were not advised to attend to their nasal cav-ity as we wished to simplify the task for the patient and haveonly one area of focus for detecting vibration. Once the patientachieved this, they were asked to take a breath, sustain a humuntil they felt vibration, and stop. Next, the patient was askedto take a breath, sustain a hum until they felt phonation, andthen sustain /i/ while feeling for vibration on their closed teeth.Once the patients were able to sustain the /mi/, they were askedto add a /a/ at the end. When the patients were able to do this,they sustained the resonant /a/ for 2–3 seconds while it was re-corded. That is, the patients said /mia/ and sustained the lastphoneme for acoustic analysis.

The MDVP Model 5105 (KayPENTAX, Montvale, NJ) cou-pled with a condenser head-mount microphone (AKG C420,Acoustics Harman Pro GmbH,Munich, Germany) held at a dis-tance of 4 cm and an angle of 45� from the participant’s mouthwas used to record the acoustic signal. Before acoustic record-ings, a trial of phonation was captured, and the gain was ad-justed to prevent peak clipping and maximize the use of thedynamic range. Recordings judged as unrepresentative of theparticipants’ true voice quality or those not following protocolwere excluded. Recordings were verified for Type I status as tobe applicable for acoustic analysis.16 The acoustic signalswere analyzed for Fo, jitter (relative average perturbation[RAP]), shimmer (Shim), NHR, and VTI using MDVP.

Analysis

McNemar’s test for matched pairs and paired t test were used toassess whether statistically significant differences in the acous-

tic analysis measures were achieved. The MDVP normativethresholds were used to group patients into categories: withinnormal limits or outside normal limits for analysis using theMcNemar’s test for matched pairs.

RESULTS

Do the acoustic analysis parameters of frequency

and amplitude perturbation, NHR, and VTI differ

before and after a voice stimulability trial?

Overall, the RAP and Shim measures were improved during thestimulability trial from the initial recordings (Figures 1–4). Theprestimulability habitual pitch average RAP measure of 1.38%was reduced to an average poststimulability measure of 0.68%.The average prestimulability habitual pitch Shim measure of3.9% was reduced to an average of 2.7% when measured post-stimulability trial. For NHR, the prestimulability habitual pitchaverage NHR measure was 0.116, and poststimulability trial,the NHR measure was 0.115. Although the average NHR didnot change, the range of NHR measures was reduced andmore closely approximated the mean. The prestimulabilityhabitual pitch average VTI measure was 0.0267, and poststi-mulability trial, the VTI measure was 0.0325. Paired t testsfor comparing pretask and posttask acoustic analysis measuresrevealed statistically significant differences at the 0.05 level forRAP (P¼ 0.001) and Shim (P¼ 0.002). Statistically signifi-cant differences were not found for NHR (P¼ 0.08) or VTI(P¼ 0.938) pre- and posttask.

A review of the data based on the normative threshold usedby MDVP was completed. The normative threshold valuesare 0.68% for RAP, 3.81% for Shim, 0.19 for NHR, and0.061 for VTI. The results were assessed for the percent of pa-tients who were outside the normative threshold for pretaskhabitual phonation. For RAP, Shim, NHR, and VTI, 72%,36%, 8%, and 0%, respectively, were outside normal limits pre-task (Figure 5). Posttask, 61%, 77%, and 100% of these phona-tions changed from being outside to inside normal limits forRAP, Shim, and NHR, respectively (Figure 6). Results demon-strated a significant change from pre- to posttrial, as indicated

FIGURE 2. Box plot of Shim during the four tasks: pretask habitual


FIGURE 4. Box plot of VTI during the four tasks: pretask habitual



by the objective measure transitioning from being outside towithin normal limits, in 75% of patients (P¼ 0.00003,McNemar’s test for matched pairs). Eighteen patients hadRAP measures above threshold levels prestimulability trial,and 11 of those patients had RAP measures below thresholdlevels poststimulability trial. Nine patients had Shim measuresabove threshold levels prestimulability trial, and seven of thosepatients had Shim measures below threshold levels poststimul-ability trial. The bench mark of the measure crossing the thresh-old is a stringent one, but it is also the most visually appealing(from red to green inMDVP).When less rigid criterion of a pos-itive change in one or more of the acoustic measures evaluatedis used, 96% of patients noted improvements.

Is the change of Fo during the stimulability trial

responsible for the changes in acoustic analysis

measures between pre- and poststimulability trial

recordings?

The average Fo for the four tasks for habitual, high, low, andunloaded tasks was 193, 317, 157, and 218 Hz, respectively

FIGURE 3. Box plot of NHR during the four tasks: pretask habitual


(Figure 7). Paired t tests for comparing pretask and posttaskacoustic analysis measures revealed statistically significant dif-ferences at the 0.05 level for Fo (P¼ 0.001). Differences in theaverage RAP measures for habitual, high, low, and unloadedtasks were 1.31%, 1.46%, 1.42%, and 0.62%, respectively. Dif-ferences in the average Shim measures for habitual, high, low,and unloaded tasks were 3.8%, 3.82%, 3.79%, and 2.5%, re-spectively. Differences in the average NHR measures for habit-ual, high, low, and unloaded tasks were 0.116, 0.116, 0.133, and0.113, respectively. Paired t tests for comparing posttask habit-ual phonation and pretask high pitch phonation revealed statis-tically significant differences for Fo (P¼ 0.000), RAP(P¼ 0.000), and Shim (P¼ 0.017). NHR and VTI did not re-veal such differences at 0.942 and 0.574, respectively. Pairedt tests for comparing posttask habitual phonation and pretasklow pitch phonation revealed statistically significant differ-ences at the 0.05 level for Fo (P¼ 0.000), RAP (P¼ 0.000),Shim (P¼ 0.007), and NHR (P¼ 0.012). VTI did not revealsuch differences (P¼ 0.51).

DISCUSSION

Do the acoustic analysis parameters of frequency

and amplitude perturbation, NHR, and VTI differ

before and after voice stimulability trials?

The recordingsmade poststimulability trial had improved acous-tic analysis measures compared with the recordings made pres-timulability trial. In most cases, this difference was significantenough to move the analysis measure from above normal limits(red) to within normal limits (green). This change is importantfor a mastery experience for three reasons: (1) acoustic analysisallows the patients to be able to immediately see a difference intheir measures during the voice evaluation, (2) acoustic analysisrecordings can be replayed to give the patients the chance tolisten to and evaluate their voice, and (3) acoustic analysis allowsthe clinician to test treatment approaches in an easily document-able manner. The quick positive feedback for patients is impor-tant for a mastery experience to increase patient’s self-efficacy,establish the credibility of the treatment, and motivate the

FIGURE 5. Example of a screen print from a prestimulability acoustic analysis demonstrating scores outside normal limits (red) on a number of

acoustic parameters.


patient to adhere to an at-home therapy regimen. The masteryexperience has been charged as the best way to improve self-efficacy, which, in turn, has shown to be a strong positive predic-tor of behavioral change.

Is the change of Fo during the stimulability trial

responsible for the changes in acoustic analysis

measures between pre- and poststimulability trial

recordings?

The recordings made poststimulability trial have improvedacoustic analysis measures compared with the habitual pitch.Given this significant finding, it was necessary to evaluatethat the cause of the change was because of the forward focusedvoice quality and not because of the change in pitch in the pre-and posthabitual phonations. To achieve this, we compared theacoustic parameters achieved during the posttrial habitual pitchwith those from the high pitch and low pitch recordings madeprestimulability trials. We found an advantage to the forwardfocused technique beyond high or low pitch change alone.Although the Fo on averagewas higher for the poststimulabilitytrial recordings than the habitual prestimulability trial record-ings, it does not appear that the positive changes in the acousticanalysis measures of perturbation are a result of a change inpitch. This interpretation of the findings is most strongly

supported by a comparison of acoustic analysis measuresfrom the prestimulability trial high pitch recordings and thepoststimulability habitual phonations. This point of evaluationis most important because it has been noted that many patientsincrease their Fo when performing forward focused voice exer-cises. The finding of higher perturbation in the high pitch com-pared with the posttrial recordings indicates that the task benefitwas not just from the increased Fo. Furthermore, many patientsnoted a decreased pitch as part of their voice disorder, so an in-crease in the Fo in the poststimulability acoustic analysis re-cordings may be another indication of improved voice quality.

Limitations

One shortcoming of the study was the absence of a direct con-trol of intensity. The intensity of the microphone was set foreach patient in the pretask habitual pitch condition and wasnot changed for the other pretask or the posttask recordings.Therefore, although exact measures of intensity were not taken,a relative measure of similarity between the two productionsoccurred. That is, a louder phonation, which would have causedpeak clipping, did not occur. Similarly, a softer phonation,which would have indicated a low signal and would not be idealfor acoustic analysis measures, did not occur.

FIGURE 6. Example of a screen print from a poststimulability acoustic analysis demonstrating a change from Figure 5 with parameters that were

outside normal limits (red) and now within normal limits (green).


There was no follow-through on patient adherence to therapyor patient outcomewith voice therapy. This study was limited toa ‘‘proof of concept’’ analysis to examine whether a stimulabil-ity trial (forward focused voice) measured by acoustic analysis

FIGURE 7. Box plot of Fo during the four tasks: pretask habitual


(objective measures and visual biofeedback) was successful atproviding positive feedback and a mastery experience for mostpatients. There is a need to follow-up this study with research toevaluate whether having this positivemastery experience has animpact on self-efficacy, treatment adherence, and treatmentoutcomes.Several factors may contribute to a patient mastery experi-

ence and improved self-efficacy. Some factors come from theuse of the forward focused voice task, which provides manyfeedback mechanisms: oral vibratory sensation, reduced laryn-geal tension, and change in voice quality. Other factors are fromthe multiple benefits of using acoustic analysis in that it affordsthe ability to replay the phonation, provides objectivemeasures,and visual biofeedback. An attempt to specifically report if anyof these possible mechanisms alone would provide a masteryexperience is not been possible, given this research design.

CONCLUSIONS

The results of this study demonstrate that a stimulability trial offorward focused voice significantly improves acoustic analysismeasures of perturbation in most patients. Given this, it is likelythat pairing acoustic analysis with forward focused voice would


provide a mastery experience for patients during their voiceevaluation. Because a mastery experience is the strongest wayto increase self-efficacy, it is possible that it would encouragepatients to be diligent in their therapy exercises at home andhelp establish confidence in the voice therapy process. Furtherstudy is needed to test the usefulness of stimulability trials withother treatment techniques. This line of research would alsobenefit from a study of long-term follow-up data on the differ-ence in the outcomes (voice, exercise consistency, therapyfollow-through) of patients who receive and do not receivestimulability trials with acoustic analysis used for visual feed-back to create a mastery experience.

Acknowledgments

The authors express their appreciation to Dr Gregory Postmafor his contribution to the data collection and clinical assess-ment of the participants. They also express their appreciationto Dr Paul Nietert for his statistical analysis consultation and re-view of the manuscript. This research was supported in part byKL2 UL1 RR029880 National Institutes of Health/NationalCenter for Research Resources.

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