Outcome of Resonant Voice Therapy for Female Teachers With Voice Disorders: Perceptual, Physiological, Acoustic, Aerodynamic, and Functional Measurements

Teachers have a high percentage of voice problems. For voice disordered teachers, resonant voice therapy is hypothesized to reduce voice problems. No research has been done on the physiological, acoustic, and aerodynamic effects of resonant voice therapy for school teachers. The purpose of this study is to investigate resonant voice therapy outcome from perceptual, physiological, acoustic, aerodynamic, and functional aspects for female teachers with voice disorders. A prospective study was designed for this research. The research subjects were 24 female teachers in Taipei. All subjects received resonant voice therapy in groups of 4 subjects, 90 minutes per session, and 1 session per week for 8 weeks. The outcome of resonant voice therapy was assessed from auditory perceptual judgment, videostroboscopic examination, acoustic measurements, aerodynamic measurements, and functional measurements before and after therapy. After therapy the severity of roughness, strain, monotone, resonance, hard attack, and glottal fry in auditory perceptual judgments, the severity of vocal fold pathology, mucosal wave, amplitude, and vocal fold closure in videostroboscopic examinations, phonation threshold pressure, and the score of physical scale in the Voice Handicap Index were significantly reduced. The speaking Fo, maximum range of speaking Fo, and maximum range of speaking intensity were significantly increased after therapy. No significant change was found in perturbation and breathiness measurements after therapy. Resonant voice therapy is effective for school teachers and is suggested as one of the therapy approaches in clinics for this population.     

Prevalence of voice problems in teachers

Teachers are frequently cited as experiencing a high rate of vocal dysfunction (1–7). Despite considerable research in the area of voice problems in teachers, the prevalence of voice disorders in this group is unknown. This study investigated the prevalence of self-reported voice problems in teachers using a mail survey of a simple random sample of 1168 state school teachers (preschool-Grade 12) in South Australia. As part of the survey, teachers were asked to report voice problems for the day of the survey, during the current teaching year, and during their careers. The response rate was 75%, with 16% of teachers reporting voice problems on the day of the survey, 20% reporting problems during the current teaching year, and 19% reporting problems at some time during their career. Females were twice as likely as males to report voice problems. These findings clearly indicate a need for further investigation of the causes of vocal dysfunction in teachers and for the development of educational programs aimed at preventing voice problems in this group of professional voice users.     

Effects of sound-field frequency modulation amplification on reducing teachers'' sound pressure level in the classroom

Voice problems are a frequent difficulty that teachers experience. Common complaints by teachers include vocal fatigue and hoarseness. One possible explanation for these symptoms is prolonged elevations in vocal loudness within the classroom. This investigation examined the effectiveness of sound-field frequency modulation (FM) amplification on reducing the sound pressure level (SPL) of the teacher's voice during classroom instruction. Specifically, SPL was examined during speech produced in a classroom lecture by 10 teachers with and without the use of sound-field amplification. Results indicated a significant 2.42-dB decrease in SPL with the use of sound-field FM amplification. These data support the use of sound-field amplification in the vocal hygiene regimen recommended to teachers by speech-language pathologists.     

Psychosocial Impact of the Teacher''s Voice Throughout the Career

It is generally accepted that vocal performance decreases with age. This decrease can be expected to be more pronounced in voice loading professions, which may lead to occupational dysphonia. The aim of this study was to investigate the course of voice complaints, experienced handicap, and absenteeism of work due to voice problems throughout the teaching years. Questionnaires were distributed among teachers of primary and secondary education, and 1875 were analyzed. The questionnaire was designed in such a way that personal aspects and questions about periods with symptoms and absence from work were included. The Voice Handicap Index (VHI) developed by Jacobson et al was sent along with the questionnaire. Surprisingly, a significant decrease of voice complaints during the career of the teachers was observed. The expectation that the percentage of teachers with a history of voice problems should experience more psychosocial impact, measured with the VHI, along their professional career could not be confirmed by this study. These results indicate that serious attention has to be paid to teachers with voice complaints. The fact that teachers in the beginning of their career complain more than in the end of their career emphasizes the importance of adequate aimed prevention programs for future teachers and for starting teachers with regard to their voice.     

The Effectiveness of Group Therapy for Students With Mild Voice Disorders: A Controlled Clinical Trial

Previous studies of students studying to be teachers have indicated that these students commonly have voice disorders. Ideally, voice disorders should be treated before students start their work as teachers, but the resources for this treatment are often limited. This study examines whether group voice therapy is effective for teacher students. Accordingly, 20 teacher students with mild voice disorders received group voice therapy (in three small groups), whereas 20 students with similar voice disorders served as a control group and consequently did not receive voice therapy. Two out of three outcome measures (perceptual evaluation of voice quality and a questionnaire on the occurrence of vocal symptoms) indicated significant changes in the treatment group compared with the control group. No differences between groups were noted in the laryngeal status. The results suggest that group voice therapy seems to be an effective method to treat students with mild voice disorders.     

Vocal Problems Among Teachers: Evaluation of a Preventive Voice Program

Vocal education programs for teachers may prevent the emergence of vocal disorders; however, only a few studies have tried to evaluate the effectiveness of these preventive programs, particularly in the long term. Two hundred and sixty-four subjects, mostly kindergarten and primary school female teachers, participated in a course on voice care, including a theoretical seminar (120 minutes) and a short voice group therapy (180 minutes, small groups of 20 subjects). For 3 months, they had to either attend the vocal ergonomics norms and, as psychological reinforcement, they had to make out a daily report of vocal abuse, or to follow the given exercises for a more efficient vocal technique, reporting on whether the time scheduled was respected or not. The effectiveness of the course was assessed in a group of 21 female teachers through a randomized controlled study. Evaluation comprehended stroboscopy, perceptual and electro-acoustical voice analysis, Voice Handicap Index, and a course benefit questionnaire. A group of 20 teachers matched for age, working years, hoarseness grade, and vocal demand served as a control group. At 3 months evaluation, participants demonstrated amelioration in the global dysphonia rates (P=0.0003), jitter (P=0.0001), shimmer (P=0.0001), MPT (P=0.0001), and VHI (P=0.0001). Twelve months after the course, the positive effects remained, although they were slightly reduced. In conclusion, a course inclusive of two lectures, a short group voice therapy, home-controlled voice exercises, and hygiene, represents a feasible and cost-effective primary prevention of voice disorders in a homogeneous and well-motivated population of teachers.     

The Impact of Voice Disorders Among Teachers: Vocal Complaints, Treatment-Seeking Behavior, Knowledge of Vocal Care, and Voice-Related Absenteeism

Objectives

Teachers are at increased risk for developing voice disorders. Occupational risk factors have been extensively examined; however, little attention has been paid to the consequences of the vocal complaints. The objective of this study was to investigate the knowledge that teachers have about vocal care, treatment-seeking behavior, and voice-related absenteeism.

Methods

The study group comprised 994 teachers and 290 controls whose jobs did not involve vocal effort. All participants completed a questionnaire inquiring about vocal complaints, treatment-seeking behavior, voice-related absenteeism, and knowledge about vocal care. Comparisons were made between teachers with and without vocal complaints and with the control group.

Results

Teachers reported significantly more voice problems than the control population (51.2% vs 27.4%) (χ² = 50.45, df = 1, P < 0.001). Female teachers reported significantly higher levels of voice disorders than their male colleagues (38% vs 13.2%, χ² = 22.34, df = 1, P < 0.001). Teachers (25.4%) sought medical care and eventually 20.6% had missed at least 1 day of work because of voice problems. Female teachers were significantly more likely to seek medical help (χ² = 7.24, df = 1, P = 0.007) and to stay at home (χ² = 7.10, df = 1, P = 0.008) in comparison with their male colleagues. Only 13.5% of all teachers received information during their education.

Conclusions

Voice disorders have an impact on teachers' personal and professional life and imply a major financial burden for society. A substantial number of teachers needed medical help and was obligated to stay at home because of voice problems. This study strongly recommends the implementation of vocal education during the training of teacher students to prepare the vocal professional user.     

Allergic, dietary, chemical, stress, and hormonal influences in voice abnormalities

Allergic, dietary, chemical, biochemical, stress, and hormonal abnormalities have long been recognized as important factors in both abnormalities of the voice and in the general health of the professional vocalist. In recent years objective methods have become available to evaluate and treat allergic, dietary, and chemical abnormalities and to better understand the effects of stress and hormonal variations. Assessment of allergic disease is efficient and cost effective through the use of in vitro testing techniques combined with skin end point titration. This provides highly specific and objective results and leads to accurate planning of desensitization treatment. This form of treatment can be especially beneficial in the prevention of recurrent laryngitis. An accurate nutritional history provides evidence of food sensitivities that can lead to cyclical allergic-like vocal symptoms that can be prevented with the use of elimination diets and the judicious use of desensitization therapy. An adequate knowledge of the potential effects of chemical sensitivities will assist the patient in the avoidance of provocative chemical exposures. An in depth evaluation of biochemical abnormalities and a specific assessment of the nutritional status must be considered to evaluate the underlying causes of long-standing general health problems that can affect the voice. Likewise, hormonal variations are not only important in their direct effects on the vocal mechanism but in their cyclical effects on the patient's basic biochemical balance. Lastly, stress, which has long been related to problems in professional performance, is only now being fully studied to determine its actual biologic influences and these must be related to the causes of voice disturbances. Understanding all these influences and planning a rational and efficient evaluation of these potential problem areas are imperative in the complete care of the patient with voice abnormalities.     

Voice Problems of Future Speech-Language Pathologists

Students training to be educators frequently exhibit voice disorders prior to employment. To date, there exist no similar studies of future speech-language pathologists (SLPs). The study is designed as a prospective, nonrandomized survey. The objective of this study is to determine the voice problems of first year graduate students training to be SLPs. Participants were 104 first year graduate students majoring in speech-language pathology at two universities. The Quick Screen for Voice was administered. Participants who failed completed a questionnaire regarding voice problems, medical history, daily habits, and voice use. When responses further indicated voice-related problems, endoscopic examination was completed. Fourteen percent (N=15) of the participants failed the screening by demonstrating two or more abnormal voice characteristics. These included persistent glottal fry (present in all who failed), low habitual pitch, juvenile resonance, hoarse, breathy, or strained phonation, abnormally low pitch on sustained vowels, and voice breaks during the frequency range. Twelve percent (N=12) failed both the screening and follow-up questionnaire. Responses included self-reported dysphonia, medical history with voice-related side effects, difficulty with excessive voice use, and voice problems occurring daily or weekly. Endoscopic evaluation showed one participant with bilateral vocal nodules. The results suggest that voice problems among future SLPs (12%) are more common than the 3-9% reported in the general population and similar to the 11% previously reported for teachers. However, future SLP voice problems are less frequent than those reported among education majors (21%) and all college students (17%). Faculty should identify students with voice problems and emphasize optimal voice use in classroom and clinical settings.     

Work ability of teachers associated with voice disorders,stress, and the indoor environment: A questionnaire study in Finland

ObjectivesThe purpose of this study was to determine whether self-reported work ability is associated with voice disorders, stress at work, and the quality of the perceived indoor environment.Study designA cross-sectional study.MethodsWe conducted a questionnaire study of 1 198 Finnish teachers utilizing the Work Ability Score.ResultsThe Work Ability Score median was 8 (Q₁: 7, Q₃: 9), and 71% (CI 95% 69%–74%) of the subjects reported that they had good work ability. Female teachers had a significantly lower Work Ability Score than male teachers. The median number of days absent due to sickness during the previous year was 4 (Q₁: 2, Q₃: 10). Voice disorders (adjusted odds ratio (aOR) 2.44; CI95% 1.73–3.44), stress at work (rather or very much vs. not at all or little; aOR 6.53; CI95% 4.31–9.90), and poor perceived indoor environment quality (aOR 2.63; CI95% 1.86–3.71) were all clear risk factors for the Work Ability Score.ConclusionWe determined that decreased work ability in teachers is connected to voice disorders, stress at work, and poor perceived indoor environment quality. Thus, in order to better maintain teachers’ work ability, we recommend that special attention should be paid to occupational health care when there are problems in the indoor environment of teachers, and they suffer from voice disorders and stress.     

A Novel Treatment for Hypophonic Voice: Twang Therapy

A hypophonic voice, characterized perceptually as weak and breathy, is associated with voice disorders such as vocal fold atrophy and unilateral vocal fold paralysis. Although voice therapy programs for hypophonia typically address the vocal folds or the sound source, twang voice quality was examined in this study as an alternative technique for increasing vocal power by altering the epilarynx or the sound filter. OBJECTIVE: This study investigated the effect of twang production on physiologic, acoustic, and perceived voice handicap measures in speakers with hypophonia. DESIGN/METHODS: This prospective pilot study compared the vocal outcomes of six participants with hypophonia at pre- and posttreatment time points. Outcome measures included mean airflow rate, intensity in dB sound pressure level (SPL), maximum phonation time, and self-report of voice handicap. RESULTS: All subjects improved in at least three of the four vocal outcome measures. Wilcoxon signed-rank test of paired differences revealed significant differences between pre- and posttherapy group means for airflow rate, SPL, and Voice Handicap Index scores. CONCLUSION: The twang voice quality as a manipulation of the sound filter offers a clinical complement to traditional voice therapies that primarily address the sound source.     

The effect of voice amplification on occupational vocal dose in elementary school teachers

Two elementary school teachers, one with and one without a history of vocal complaints, wore a vocal dosimeter all day at school for a 3-week period. In the second week, each teacher wore a portable voice amplifier. Each teacher showed a reduction in vocal intensity during the week of amplification, with a larger effect for the teacher with vocal difficulties. This teacher also showed a decrease in hourly vocal fold distance dose as measured by the dosimeter despite incurring longer phonation times. Fundamental frequency and vocal fold cycle dose did not appear to be affected by the use of amplification during the teaching day. Both teachers showed evidence of a possible moderate effect of adjusting vocal intensity in the week after amplification, possibly as a means to recalibrate their perceived vocal loudness. This study demonstrates the usefulness of both vocal dosimetry and amplification in monitoring and modifying vocal dose in an occupational setting and reinforces previous data suggesting the effectiveness of amplification in reducing the vocal load in schoolteachers. Implications of the data for future research regarding prevention and treatment of occupational voice disorders are discussed.     

The ChatterVox™ Portable Voice Amplifier: A Means to Vibration Dose Reduction?

By speaking loudly for extended periods, teachers are vulnerable to laryngeal and voice changes associated with vocal fold “vibration overdose.” Voice clinicians frequently recommend voice amplification ostensibly designed to reduce vibration dose and improve voice. However, there are few data regarding the degree of vocal loudness attenuation achieved by specific amplification devices. The purpose of this investigation was to examine the effectiveness of the ChatterVox™ Portable Voice Amplification System (Siemens Hearing Instruments) for reducing the sound pressure level (SPL) of a speaker's voice during a simulated classroom lecture. Ten participants were instructed to continuously read one of two phonetically balanced passages while amplified and unamplified. Voice intensity measurements were obtained at three inches from the mouth (i.e., mouth level) and at the back of a classroom in both amplified and unamplified conditions. When amplified with the ChatterVox™, speakers experienced an average decrease in vocal intensity at mouth-level of 6.03 dB SPL (p < 0.002). Furthermore, an average increase of 2.55 dB SPL (p < 0.038) at the back of the classroom was observed. Collectively, these results indicate that the ChatterVox™ amplification device reduced the speaker's vocal intensity level at the microphone, while it augmented the voice heard at the back of the classroom. By inference, this degree of vocal attenuation at mouth level should contribute to a desirable reduction in vibration dose, thus lowering the risk of vibration overdose.     

Rating,ranking, and understanding acoustical quality in university classrooms

Nonoptimal classroom acoustical conditions directly affect speech perception and, thus, learning by students. Moreover, they may lead to voice problems for the instructor, who is forced to raise his/her voice when lecturing to compensate for poor acoustical conditions. The project applied previously developed simplified methods to predict speech intelligibility in occupied classrooms from measurements in unoccupied and occupied university classrooms. The methods were used to predict the speech intelligibility at various positions in 279 University of British Columbia (UBC) classrooms, when 70% occupied, and for four instructor voice levels. Classrooms were classified and rank ordered by acoustical quality, as determined by the room-average speech intelligibility. This information was used by UBC to prioritize classrooms for renovation. Here, the statistical results are reported to illustrate the range of acoustical qualities found at a typical university. Moreover, the variations of quality with relevant classroom acoustical parameters were studied to better understand the results. In particular, the factors leading to the best and worst conditions were studied. It was found that 81% of the 279 classrooms have "good," "very good," or "excellent" acoustical quality with a "typical" (average-male) instructor. However, 50 (18%) of the classrooms had "fair" or "poor" quality, and two had "bad" quality, due to high ventilation-noise levels. Most rooms were "very good" or "excellent" at the front, and "good" or "very good" at the back. Speech quality varied strongly with the instructor voice level. In the worst case considered, with a quiet female instructor, most of the classrooms were "bad" or "poor." Quality also varies with occupancy, with decreased occupancy resulting in decreased quality. The research showed that a new classroom acoustical design and renovation should focus on limiting background noise. They should promote high instructor speech levels at the back of the classrooms. This involves, in part, limiting the amount of sound absorption that is introduced into classrooms to control reverberation. Speech quality is not very sensitive to changes in reverberation, so controlling it for its own sake should not be a design priority.     

Evaluation of Voice Pathology Based on the Estimation of Vocal Fold Biomechanical Parameters

Voice disorders are a source of increasing concern as normal voice quality is a social demand for at least one third of the population in developed countries in cases where voice is an essential resource in professional exercise. In addition, the growing exposure to certain pathogenic factors such as smoking, alcohol abuse, air pollution, and acoustic contamination, and other problems such as gastro-esopharyngeal reflux or allergy as well as aging, aggravate voice disorders. Voice pathologies justify the assignment of larger resources to prevention policies, early detection, and less aggressive treatments. Traditional pathology detection relies on perceptive evaluation methods (GRABS), acoustic analysis, and visual inspection (indirect laryngoscopy, and modern fibro-endo-stroboscopy). This article describes a method for voice pathology detection based on the noninvasive estimation of vocal cord biomechanical parameters derived from voice using specific signal processing methods. Preliminary results using records from patients showing four frequent causes of voice pathology (nodules, polyps, chronic laryngitis, and Reinke's edema) are given. The results show that the alteration (distortion, unbalance, or deviation) of cord biomechanical parameters may serve as an indicator of pathology. Statistical methods based on hierarchical clustering and principal component analysis reveal that combining biomechanical estimates with classic perturbation parameters increases the accuracy of acoustic analysis, improving the detection of voice pathology. This research could open new possibilities for noninvasive screening of vocal fold pathologies and could be used in the implantation of e-health voice care services.     

The Prevalence of Voice Disorders Among Day Care Center Teachers Compared with Nurses: A Questionnaire and Clinical Study

The acceptance of voice disorders by day care center teachers as an occupational disease is not an invariably established practice. This is due to the lack of reliable evidence of a higher risk for voice disorders in this profession. To find out the risk of voice disorders, an epidemiological study was conducted among day care center teachers (n = 262), using hospital nurses (n = 108) as a control group. Symptoms were charted by a questionnaire. In a clinical examination made by a laryngologist, the voice quality was assessed and the laryngeal status noted. Teachers at day care centers had significantly more voice disorders than did nurses. Vocal nodules and laryngitis findings appeared significantly more frequently among day care center teachers than among those in the control group. The results prove voice disorders to be more frequent among day care center teachers than among control group subjects, and also that the main cause for this may be a higher vocal loading among day care center teachers than among control group subjects.     

Epidemiological Study of Voice Disorders Among Teaching Professionals of La Rioja, Spain

The purpose of the present study was to calculate the prevalence and incidence of voice disorders among teaching staff and find out the associated occupational risk factors. A case-control study was performed with 905 teachers, 579 cases and 326 controls; 492 were randomly selected and 413 volunteered. All teachers were asked to fill out a standard questionnaire. Next, a complete laryngeal exam was performed including a general ear, nose, and throat evaluation and videolaryngostroboscopy. The prevalence of voice disorders among teaching staff was 57%. The most prevalent lesions were vocal overstrain (18%), nodular lesions (14%), and hyperfunctional dysphonia (8%). The incidence rate was 3.87 new cases per year per 1000 teachers. Women had organic lesions three times more than men (odds ratio [OR]: 3.52, confidence interval [CI]: 2.04-6.09). However, men had chronic laryngitis three times more than women (OR: 2.93, CI: 1.50-5.71) and functional dysphonia nearly twice more than women (OR: 1.81, CI: 1.21-2.69). We find a significant risk of suffering voice disorders in teachers who smoke daily (OR: 2.31, CI: 1.58-3.37) and who drink several cups of coffee or tea (OR: 1.87, CI: 1.36-2.56). It is advisable to carry out an annual evaluation of all teaching staff on account of the high prevalence of voice disorders among them.     

Impact and Prevention of Voice Problems in the Teaching Profession: Embracing the Consumers'' View

Teachers are vulnerable to developing voice problems due to their specific occupational demands during teaching. Information on how the teaching profession is impacted by voice problems and what the profession perceives to be useful information for preventing voice problems is important for health care service providers. A total of 122 subjects from the teaching profession (55 practicing teachers and 67 prospective teachers) were therefore surveyed to ascertain their perception of their voice condition and the impact of voice problems on their communication, social life, personal emotions, and occupation. The results showed that the practicing teachers perceived their voice to be significantly worse than the prospective teachers. In addition, the teachers also faced significantly more difficulties in their daily communication than the prospective teachers. These two groups of subjects believed that information on breathing exercises and specific vocal hygiene strategies would help them prevent voice problems.     

Development of an Auditory-Perceptual Rating Instrument for the Operatic Singing Voice

Although considerable progress has been made in the development of acoustic and physiological measures of operatic singing voice, there is still no widely accepted objective tool for the evaluation of its multidimensional features. Auditory-perceptual evaluation, therefore, remains an important evaluation method for singing pedagogues, voice scientists, and clinicians who work with opera singers. Few investigators, however, have attempted to develop standard auditory-perceptual tools for evaluation of the operatic voice. This study aimed to pilot test a new auditory-perceptual rating instrument for operatic singing voice. Nine expert teachers of operatic singing used the instrument to rate the singing voices of 21 professional opera chorus artists from a national opera company. The findings showed that the instrument has good face validity, that it can be legitimately treated as a psychometrically sound scale, and that raters can use the scale consistently, both between and within judges. This new instrument, therefore, has the potential to allow opera singers, their teachers, voice care clinicians, and researchers to evaluate the important auditory-perceptual features of operatic voice quality.     

Prevalence of voice disorders among future teachers

An epidemiological study was conducted in order to find out the prevalence of voice disorders among students studying to be teachers. Vocal symptoms were inquired of 226 students. Their voices were assessed perceptually by a speech therapist and those who had abnormal voice quality or reported several vocal symptoms were referred to a clinical examination by a laryngologist. The results showed that 20% of this population reported two or more vocal symptoms during the previous year and that 19% had an organic voice disorder. This reinforces the need for clinical evaluation of students with vocal symptoms and more vocal training in the teacher education programs.