Voice Disorders
Conditions
Keywords
Voice training, Education, Voice, Faculty
Brief summary
The purpose of this study is to verify the effects of two speech-pathology interventions: vocal warm-up and respiratory training in teachers who work in a public school of the city of Salvador-Bahia, with or without complaints of vocal disorders. It is a preventive study and the hypothesis is that both approaches can produce positive voice changes, but the Vocal Warm-up will produce the most significant changes.
Detailed description
Randomized Clinical Trial where participants were allocated into groups: Vocal Warm-up (to perform exercises of resistance and flexibility for 13 minutes before teaching, during six weeks) and Respiratory Muscle Training (to perform exercises to strengthen the respiratory muscles through the use of incentive respiratory equipment. Five repetitions of exhales with an interval of thirty seconds between each one were performed. It was requested rest for two minutes, repeating the procedure four times with the total of five series. These exercises were performed for 13 minutes before teaching, during six weeks). Outcomes analyzed: demographics and teaching activity characteristics; symptoms, habits and factors associated with voice disorders; self-reported voice handicap (Voice Handicap Index-VHI-10); vocal severity rating (Vocal Severity Scale); and acoustic parameters through the computerized acoustic voice analysis program VoxMetria (CTS Informatics).
Interventions
BEHAVIORALVocal Warm-up
Vocal Warm-up group performed 13 minutes of vocal warm-up exercises everyday before teaching over a course of 6 weeks, with one session exercise per day.
BEHAVIORALRespiratory Muscle Training
Respiratory Muscle Training group performed 13 minutes of Respiratory Muscle Training everyday before teaching over a course of 6 weeks, with one session exercise per day.
Sponsors
Bahia State Secretariat of Education, Brazil
Federal University of Bahia
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Age between 20-60. * No occurence of speech therapy simultaneously to the intervention
Exclusion criteria
* Professional voice use in another activity; * Frequent use of alcohol and tobacco; * Influenza and/or upper respiratory tract infections (eg, rhinitis, sinusitis, pharyngitis) during the period of participation in the research.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in GNE | Baseline, 6 weeks | Glottal to Noise Excitation ratio (GNE) is an acoustic measurement to calculate the noise in a series of pulses produced by the oscillation of the vocal folds. This parameter is based on the hypothesis that resulting pulses of vocal fold collision generate a synchronous excitation of different frequency bands. Moreover, the noise produced by the vocal folds compressed generates uncorrelated excitations. Normal levels \> 0.5 dB |
| Change in Fundamental Frequency | Baseline, 6 weeks | The measurement of fundamental frequency directly reflects the rate of vibration of the vocal folds. The fundamental frequency term refers to the frequency of more occurrence of vocal fold vibration, featuring a certain production. |
| Change in Jitter | Baseline, 6 weeks | Jitter is the perturbation cycle-to-cycle of the fundamental frequency. High levels of jitter are normally associated with pathological voice. The instability of the fundamental frequency can be attributed to changes in size, shape or firmness of the vocal folds. Normal values must be \< 0.6%. |
| Change in Shimmer | Baseline, 6 weeks | Shimmer measures the amplitude perturbations, e. g. how fast the amplitude changes on a sustained vowel for a few seconds. Shimmer high levels are normally associated with pathological voice. This can be attributed due to changes in size, shape or firmness of the vocal folds. Normal values \< 6.5% |
| Change in Noise | Baseline, 6 weeks | Noise is the analysis of aperiodic components of the sound's signal. It is an important correlate of that the human ear considers voice disorders. Normal levels \< 2.5 dB |
| Voice Handicap Index (VHI-10) | Baseline, 6 weeks | The voice handicap index (VHI) is a self-assessment questionnaire which quantifies the functional, physical and emotional impacts of a voice disorder on the quality of life. The VHI-10 is a reduced version and it consists of 10 questions about the severity of the voice problem perceived by the subject. It is presented as an ordinal scale (range 0-4) that indicates how frequently the subject has experienced the same situation (0 = never; 1 = almost never; 2 = sometimes; 3= almost always; 4 = always). Total VHI Score ranges from 0 (never) to 40 (always). Higher scores indicate greater voice handicap. Abnormal values \> 11. |
| Acoustic Analysis (Fundamental Frequency) | Baseline, 6 weeks | The measurement of fundamental frequency directly reflects the rate of vibration of the vocal folds. The fundamental frequency term refers to the frequency of more occurrence of vocal fold vibration, featuring a certain production. |
| Acoustic Analysis (Jitter) | Baseline, 6 weeks | Jitter is the perturbation cycle-to-cycle of the fundamental frequency. High levels of jitter are normally associated with pathological voice. The instability of the fundamental frequency can be attributed to changes in size, shape or firmness of the vocal folds. Normal values must be \< 0.6%. |
| Acoustic Analysis (Shimmer) | Baseline, 6 weeks | The shimmer measures the amplitude's disturbance, e. g. how fast the amplitude changes on a sustained vowel for a few seconds. Shimmer high levels are normally associated with pathological voice. This can be attributed due to changes in size, shape or firmness of the vocal folds. Normal values \< 6.5%. |
| Acoustic Analysis (Noise) | Baseline, 6 weeks | Noise is the analysis of aperiodic components of the sound's signal. It is an important correlate of that the human ear considers voice disorders. Normal levels \< 2.5 dB |
| Acoustic Analysis (GNE) | Baseline, 6 weeks | Glottal to Noise Excitation ratio (GNE) is an acoustic measurement to calculate the noise in a series of pulses produced by the oscillation of the vocal folds. This parameter is based on the hypothesis that resulting pulses of vocal fold collision generate a synchronous excitation of different frequency bands. Moreover, the noise produced by the vocal folds compressed generates uncorrelated excitations. Normal levels \> 0.5 dB |
| Voice Handicap Index (VHI-10) 2 | Baseline, 6 weeks | The voice handicap index (VHI) is a self-assessment questionnaire which quantifies the functional, physical and emotional impacts of a voice disorder on the quality of life. The VHI-10 is a reduced version and it consists of 10 questions about the severity of the voice problem perceived by the subject. It is presented as an ordinal scale (range 0-4) that indicates how frequently the subject has experienced the same situation (0 = never; 1 = almost never; 2 = sometimes; 3= almost always; 4 = always). Total VHI Score ranges from 0 (never) to 40 (always). Higher scores indicate greater voice handicap. Abnormal values \> 11. |
| Acoustic Analysis (Fundamental Frequency) 2 | Baseline, 6 weeks | The measurement of fundamental frequency directly reflects the rate of vibration of the vocal folds. The fundamental frequency term refers to the frequency of more occurrence of vocal fold vibration, featuring a certain production. |
| Acoustic Analysis (Jitter) 2 | Baseline, 6 weeks | Jitter is the perturbation cycle-to-cycle of the fundamental frequency. High levels of jitter are normally associated with pathological voice. The instability of the fundamental frequency can be attributed to changes in size, shape or firmness of the vocal folds. Normal values must be \< 0.6%. |
| Acoustic Analysis (Shimmer) 2 | Baseline, 6 weeks | The shimmer measures the amplitude's disturbance, e. g. how fast the amplitude changes on a sustained vowel for a few seconds. Shimmer high levels are normally associated with pathological voice. This can be attributed due to changes in size, shape or firmness of the vocal folds. Normal values \< 6.5%. |
| Acoustic Analysis (Noise) 2 | Baseline, 6 weeks | Noise is the analysis of aperiodic components of the sound's signal. It is an important correlate of that the human ear considers voice disorders. Normal levels \< 2.5 dB |
| Acoustic Analysis (GNE) 2 | Baseline, 6 weeks | Glottal to Noise Excitation ratio (GNE) is an acoustic measurement to calculate the noise in a series of pulses produced by the oscillation of the vocal folds. This parameter is based on the hypothesis that resulting pulses of vocal fold collision generate a synchronous excitation of different frequency bands. Moreover, the noise produced by the vocal folds compressed generates uncorrelated excitations. Normal levels \> 0.5 dB |
| Change in Voice Handicap Index (VHI-10) | Baseline, 6 weeks | The voice handicap index (VHI) is a self-assessment questionnaire which quantifies the functional, physical and emotional impacts of a voice disorder on the quality of life. The VHI-10 is a reduced version and it consists of 10 questions about the severity of the voice problem perceived by the subject. It is presented as an ordinal scale (range 0-4) that indicates how frequently the subject has experienced the same situation (0 = never; 1 = almost never; 2 = sometimes; 3= almost always; 4 = always). Total VHI Score ranges from 0 (never) to 40 (always). Higher scores indicate greater voice handicap. Abnormal values \> 11. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Post-treatment Questionnaire (Voice Clearer) | After 6 weeks of intervention | The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their extent of improvement on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). The results were presented in frequency/percentage of subjects that answered moderate/a lot in each intervention. |
| Post-treatment Questionnaire (Easier to Talk) | After 6 weeks of intervention | The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their extent of improvement on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). The results were presented in frequency/percentage of subjects that answered moderate/a lot in each intervention. |
| Post-treatment Questionnaire (Compliance With Intervention) | After 6 weeks of intervention | The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their degree of compliance on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). It was considered compliance the answers moderate and a lot in comparison of not at all/somewhat, considered as no compliance. The results were presented in frequency/percentage of subjects in each intervention. |
| Post-treatment Questionnaire (Voice Symptoms Improvement) | After 6 weeks of intervention | The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their extent of improvement on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). The results were presented in frequency/percentage of subjects that answered moderate/a lot in each intervention. |
Countries
Brazil
Participant flow
Recruitment details
The population sample was selected by convenience criteria. All the school's teachers were invited to participate and were selected according to eligibility criteria in the beginning of the study.
Participants by arm
| Arm | Count |
|---|---|
| Vocal Warm-up Vocal Warm up group was performed during 13 minutes of vocal warm-up exercises everyday before teaching over a course of 6 weeks, with one session exercise per day. | 14 |
| Respiratory Muscle Training Respiratory Muscle Training group was performed during 13 minutes of Respiratory Muscle Training everyday before teaching over a course of 6 weeks, with one session exercise per day. | 17 |
| Total | 31 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Withdrawal by Subject | 6 | 4 |
Baseline characteristics
| Characteristic | Vocal Warm-up | Respiratory Muscle Training | Total |
|---|---|---|---|
| Age, Continuous | 45.8 years STANDARD_DEVIATION 8.1 | 43.6 years STANDARD_DEVIATION 11.4 | 44.6 years STANDARD_DEVIATION 9.9 |
| Sex: Female, Male Female | 12 Participants | 12 Participants | 24 Participants |
| Sex: Female, Male Male | 2 Participants | 5 Participants | 7 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 20 | 0 / 21 |
| serious Total, serious adverse events | 0 / 20 | 0 / 21 |
Outcome results
Primary
Acoustic Analysis (Fundamental Frequency)
The measurement of fundamental frequency directly reflects the rate of vibration of the vocal folds. The fundamental frequency term refers to the frequency of more occurrence of vocal fold vibration, featuring a certain production.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Fundamental Frequency) | 191.87 Hertz (Hz) | Standard Deviation 43.35 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Fundamental Frequency) | 185.71 Hertz (Hz) | Standard Deviation 33.7 |
p-value: 0.345Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Fundamental Frequency) 2
The measurement of fundamental frequency directly reflects the rate of vibration of the vocal folds. The fundamental frequency term refers to the frequency of more occurrence of vocal fold vibration, featuring a certain production.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Fundamental Frequency) 2 | 196.21 Hertz (Hz) | Standard Deviation 34.47 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Fundamental Frequency) 2 | 186.25 Hertz (Hz) | Standard Deviation 31.53 |
p-value: 0.049Wilcoxon's signed-rank test
Primary
Acoustic Analysis (GNE)
Glottal to Noise Excitation ratio (GNE) is an acoustic measurement to calculate the noise in a series of pulses produced by the oscillation of the vocal folds. This parameter is based on the hypothesis that resulting pulses of vocal fold collision generate a synchronous excitation of different frequency bands. Moreover, the noise produced by the vocal folds compressed generates uncorrelated excitations. Normal levels \> 0.5 dB
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (GNE) | 0.88 Decibel (dB) | Standard Deviation 0.11 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (GNE) | 0.88 Decibel (dB) | Standard Deviation 0.11 |
p-value: 0.477Wilcoxon's signed-rank test
Primary
Acoustic Analysis (GNE) 2
Glottal to Noise Excitation ratio (GNE) is an acoustic measurement to calculate the noise in a series of pulses produced by the oscillation of the vocal folds. This parameter is based on the hypothesis that resulting pulses of vocal fold collision generate a synchronous excitation of different frequency bands. Moreover, the noise produced by the vocal folds compressed generates uncorrelated excitations. Normal levels \> 0.5 dB
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (GNE) 2 | 0.89 Decibel (dB) | Standard Deviation 0.12 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (GNE) 2 | 0.92 Decibel (dB) | Standard Deviation 0.06 |
p-value: 0.959Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Jitter)
Jitter is the perturbation cycle-to-cycle of the fundamental frequency. High levels of jitter are normally associated with pathological voice. The instability of the fundamental frequency can be attributed to changes in size, shape or firmness of the vocal folds. Normal values must be \< 0.6%.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Jitter) | 0.19 percentage of jitter | Standard Deviation 0.14 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Jitter) | 0.45 percentage of jitter | Standard Deviation 0.94 |
p-value: 0.171Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Jitter) 2
Jitter is the perturbation cycle-to-cycle of the fundamental frequency. High levels of jitter are normally associated with pathological voice. The instability of the fundamental frequency can be attributed to changes in size, shape or firmness of the vocal folds. Normal values must be \< 0.6%.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Jitter) 2 | 0.14 percentage of jitter | Standard Deviation 0.11 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Jitter) 2 | 0.10 percentage of jitter | Standard Deviation 0.05 |
p-value: 0.323Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Noise)
Noise is the analysis of aperiodic components of the sound's signal. It is an important correlate of that the human ear considers voice disorders. Normal levels \< 2.5 dB
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Noise) | 0.72 Decibel (dB) | Standard Deviation 0.46 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Noise) | 0.72 Decibel (dB) | Standard Deviation 0.44 |
p-value: 0.451Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Noise) 2
Noise is the analysis of aperiodic components of the sound's signal. It is an important correlate of that the human ear considers voice disorders. Normal levels \< 2.5 dB
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Noise) 2 | 0.69 Decibel (dB) | Standard Deviation 0.5 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Noise) 2 | 0.68 Decibel (dB) | Standard Deviation 0.5 |
p-value: 0.776Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Shimmer)
The shimmer measures the amplitude's disturbance, e. g. how fast the amplitude changes on a sustained vowel for a few seconds. Shimmer high levels are normally associated with pathological voice. This can be attributed due to changes in size, shape or firmness of the vocal folds. Normal values \< 6.5%.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Shimmer) | 2.77 percentage of shimmer | Standard Deviation 0.94 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Shimmer) | 4.19 percentage of shimmer | Standard Deviation 2.6 |
p-value: 0.022Wilcoxon's signed-rank test
Primary
Acoustic Analysis (Shimmer) 2
The shimmer measures the amplitude's disturbance, e. g. how fast the amplitude changes on a sustained vowel for a few seconds. Shimmer high levels are normally associated with pathological voice. This can be attributed due to changes in size, shape or firmness of the vocal folds. Normal values \< 6.5%.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Acoustic Analysis (Shimmer) 2 | 2.90 percentage of shimmer | Standard Deviation 0.85 |
| Respiratory Muscle Training (Posttest) | Acoustic Analysis (Shimmer) 2 | 3.10 percentage of shimmer | Standard Deviation 0.97 |
p-value: 0.296Wilcoxon's signed-rank test
Primary
Change in Fundamental Frequency
The measurement of fundamental frequency directly reflects the rate of vibration of the vocal folds. The fundamental frequency term refers to the frequency of more occurrence of vocal fold vibration, featuring a certain production.
Time frame: Baseline, 6 weeks
Population: Between-group analysis (mean difference posttest minus pretest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Change in Fundamental Frequency | -9.96 Hertz (Hz) | Standard Deviation 17.14 |
| Respiratory Muscle Training (Posttest) | Change in Fundamental Frequency | -6.15 Hertz (Hz) | Standard Deviation 26.11 |
p-value: 0.3Wilcoxon (Mann-Whitney)
Primary
Change in GNE
Glottal to Noise Excitation ratio (GNE) is an acoustic measurement to calculate the noise in a series of pulses produced by the oscillation of the vocal folds. This parameter is based on the hypothesis that resulting pulses of vocal fold collision generate a synchronous excitation of different frequency bands. Moreover, the noise produced by the vocal folds compressed generates uncorrelated excitations. Normal levels \> 0.5 dB
Time frame: Baseline, 6 weeks
Population: Between-group analysis (mean difference posttest minus pretest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Change in GNE | 0.02 Decibel (dB) | Standard Deviation 0.13 |
| Respiratory Muscle Training (Posttest) | Change in GNE | 0.001 Decibel (dB) | Standard Deviation 0.67 |
p-value: 0.74Wilcoxon (Mann-Whitney)
Primary
Change in Jitter
Jitter is the perturbation cycle-to-cycle of the fundamental frequency. High levels of jitter are normally associated with pathological voice. The instability of the fundamental frequency can be attributed to changes in size, shape or firmness of the vocal folds. Normal values must be \< 0.6%.
Time frame: Baseline, 6 weeks
Population: Between-group analysis (mean difference posttest minus pretest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Change in Jitter | -0.02 percentage of jitter | Standard Deviation 0.1 |
| Respiratory Muscle Training (Posttest) | Change in Jitter | 0.25 percentage of jitter | Standard Deviation 0.89 |
p-value: 0.2Wilcoxon (Mann-Whitney)
Primary
Change in Noise
Noise is the analysis of aperiodic components of the sound's signal. It is an important correlate of that the human ear considers voice disorders. Normal levels \< 2.5 dB
Time frame: Baseline, 6 weeks
Population: Between-group analysis (mean difference posttest minus pretest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Change in Noise | -0.01 Decibel (dB) | Standard Deviation 0.14 |
| Respiratory Muscle Training (Posttest) | Change in Noise | -0.004 Decibel (dB) | Standard Deviation 0.67 |
p-value: 0.49Wilcoxon (Mann-Whitney)
Primary
Change in Shimmer
Shimmer measures the amplitude perturbations, e. g. how fast the amplitude changes on a sustained vowel for a few seconds. Shimmer high levels are normally associated with pathological voice. This can be attributed due to changes in size, shape or firmness of the vocal folds. Normal values \< 6.5%
Time frame: Baseline, 6 weeks
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Change in Shimmer | 0.20 percentage of shimmer | Standard Deviation 0.89 |
| Respiratory Muscle Training (Posttest) | Change in Shimmer | 1.41 percentage of shimmer | Standard Deviation 2.3 |
p-value: 0.77Wilcoxon (Mann-Whitney)
Primary
Change in Voice Handicap Index (VHI-10)
The voice handicap index (VHI) is a self-assessment questionnaire which quantifies the functional, physical and emotional impacts of a voice disorder on the quality of life. The VHI-10 is a reduced version and it consists of 10 questions about the severity of the voice problem perceived by the subject. It is presented as an ordinal scale (range 0-4) that indicates how frequently the subject has experienced the same situation (0 = never; 1 = almost never; 2 = sometimes; 3= almost always; 4 = always). Total VHI Score ranges from 0 (never) to 40 (always). Higher scores indicate greater voice handicap. Abnormal values \> 11.
Time frame: Baseline, 6 weeks
Population: Between-group analysis (mean difference posttest minus pretest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Change in Voice Handicap Index (VHI-10) | -8.75 units on a scale | Standard Deviation 10.13 |
| Respiratory Muscle Training (Posttest) | Change in Voice Handicap Index (VHI-10) | -6.61 units on a scale | Standard Deviation 6.84 |
p-value: 0.76Wilcoxon (Mann-Whitney)
Primary
Voice Handicap Index (VHI-10)
The voice handicap index (VHI) is a self-assessment questionnaire which quantifies the functional, physical and emotional impacts of a voice disorder on the quality of life. The VHI-10 is a reduced version and it consists of 10 questions about the severity of the voice problem perceived by the subject. It is presented as an ordinal scale (range 0-4) that indicates how frequently the subject has experienced the same situation (0 = never; 1 = almost never; 2 = sometimes; 3= almost always; 4 = always). Total VHI Score ranges from 0 (never) to 40 (always). Higher scores indicate greater voice handicap. Abnormal values \> 11.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Voice Handicap Index (VHI-10) | 20.44 units on a scale | Standard Deviation 13.7 |
| Respiratory Muscle Training (Posttest) | Voice Handicap Index (VHI-10) | 13.82 units on a scale | Standard Deviation 10.86 |
p-value: 0.001Wilcoxon's signed-rank test
Primary
Voice Handicap Index (VHI-10) 2
The voice handicap index (VHI) is a self-assessment questionnaire which quantifies the functional, physical and emotional impacts of a voice disorder on the quality of life. The VHI-10 is a reduced version and it consists of 10 questions about the severity of the voice problem perceived by the subject. It is presented as an ordinal scale (range 0-4) that indicates how frequently the subject has experienced the same situation (0 = never; 1 = almost never; 2 = sometimes; 3= almost always; 4 = always). Total VHI Score ranges from 0 (never) to 40 (always). Higher scores indicate greater voice handicap. Abnormal values \> 11.
Time frame: Baseline, 6 weeks
Population: Within-group analysis (pretest vs. posttest)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Respiratory Muscle Training (Baseline) | Voice Handicap Index (VHI-10) 2 | 21.78 units on a scale | Standard Deviation 17.44 |
| Respiratory Muscle Training (Posttest) | Voice Handicap Index (VHI-10) 2 | 13.04 units on a scale | Standard Deviation 14.18 |
p-value: 0.007Wilcoxon's signed-rank test
Secondary
Post-treatment Questionnaire (Compliance With Intervention)
The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their degree of compliance on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). It was considered compliance the answers moderate and a lot in comparison of not at all/somewhat, considered as no compliance. The results were presented in frequency/percentage of subjects in each intervention.
Time frame: After 6 weeks of intervention
Population: Between-group analysis
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Respiratory Muscle Training (Baseline) | Post-treatment Questionnaire (Compliance With Intervention) | 100 percentage of subjects |
| Respiratory Muscle Training (Posttest) | Post-treatment Questionnaire (Compliance With Intervention) | 76.5 percentage of subjects |
p-value: 0.107Fisher Exact
Secondary
Post-treatment Questionnaire (Easier to Talk)
The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their extent of improvement on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). The results were presented in frequency/percentage of subjects that answered moderate/a lot in each intervention.
Time frame: After 6 weeks of intervention
Population: Between-group analysis
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Respiratory Muscle Training (Baseline) | Post-treatment Questionnaire (Easier to Talk) | 57.2 percentage of subjects |
| Respiratory Muscle Training (Posttest) | Post-treatment Questionnaire (Easier to Talk) | 17.7 percentage of subjects |
p-value: 0.03Fisher Exact
Secondary
Post-treatment Questionnaire (Voice Clearer)
The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their extent of improvement on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). The results were presented in frequency/percentage of subjects that answered moderate/a lot in each intervention.
Time frame: After 6 weeks of intervention
Population: Between-group analysis
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Respiratory Muscle Training (Baseline) | Post-treatment Questionnaire (Voice Clearer) | 50 percentage of subjects |
| Respiratory Muscle Training (Posttest) | Post-treatment Questionnaire (Voice Clearer) | 17.7 percentage of subjects |
p-value: 0.12Fisher Exact
Secondary
Post-treatment Questionnaire (Voice Symptoms Improvement)
The post-treatment questionnaire was based on the original designed by Roy (2003) for assessing the teachers' perception of voice improvement and compliance with the intervention. Participants rated their extent of improvement on a 3-point Likert scale (not at all/somewhat; moderate; a lot). The questionnaire was applied only after the intervention. The answers were dichotomized in two categories (moderate/a lot and not at all/somewhat). The results were presented in frequency/percentage of subjects that answered moderate/a lot in each intervention.
Time frame: After 6 weeks of intervention
Population: Between-group analysis
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Respiratory Muscle Training (Baseline) | Post-treatment Questionnaire (Voice Symptoms Improvement) | 64.3 percentage of participants |
| Respiratory Muscle Training (Posttest) | Post-treatment Questionnaire (Voice Symptoms Improvement) | 11.8 percentage of participants |
p-value: 0.003Fisher Exact