Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

Adolescents’ Voice Use and Perceptions of Vocal Heath During a Five-Day School-based Choral Music Camp A Case Study Sheri Cook-Cunningham University of Kansas

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Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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Abstract This case study documented student voice use during a five day school-based choral music camp experience through (a) daily surveys of participants (N= 25) soliciting responses to seven voice health indicator statements and number of sleep hours, (b) acquisition of phonation time dose (Dt) and phonation distance dose (Dd) data from two female students who wore ambulatory phonation monitors (APMs) during waking hours each camp day and for two baseline periods (two days prior to camp and one day following camp), and (c) three administrations of the Singing Voice Handicap Index (SVHI) to the two students wearing the APMs. Student perceptions of vocal health and self-reported sleep hours were analyzed through daily and first rehearsal day/ final rehearsal day comparisons. APM data were disaggregated by camp, pre-, and post-camp days, as well as camp-related and non camp-related phonation and rehearsal and nonrehearsal camp activities during the five camp days. Results indicated no significant changes in the perception of singing voice quality for male participants who were in camp for 2 hours / day or for female participants who were in camp for 4 hours / day. Results were discussed in terms of adolescent singers’ vocal health perceptions and voice use behaviors, structuring of days-long, co-curricular choral singing experiences, and suggestions for future research.

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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Adolescent’s Voice Use and Perceptions of Vocal Health During a Five-Day School-Based Choral Music Camp A Case Study Adolescent singers have many opportunities to participate in vocal music making. During the school year, these opportunities may include several school choirs, a church choir, the school musical and perhaps even district and state choir Summer brings another opportunity for vocal involvement: summer music camps. These camps are often weeklong events with numerous music, social and recreational events. Although a growing body of research addresses adult voice use and vocal health, there is to date a scarcity of empirical data regarding voice use and vocal health perceptions among adolescent singers. Adolescence is a period marked by anatomical change as students enter and progress through puberty. It is a time in which the voice is most fragile as the larynx and vocal folds undergo considerable growth and change (Cooksey, 2000; Gackle, 2000). Data documenting adolescent phonation behaviors could prove useful to music educators, choir clinicians and music camp organizers. With nearly one quarter of the US workforce depending on their voices for their livelihood, much research has centered on occupational voice use and complaints (Hunter and Titze, 2009). Numerous studies have identified teachers as one of the highest at-risk populations for experiencing voice problems (e.g., Bernstorf & Burk, 1996, Hendry, 2001, Mattiske, et al., 1998; Roy, Merrill, Thibeault, Gray, & Smith, 2004; Russell, et al, 1998 Sapir, et al, 1993; Schwartz, 2006, Simberg, et al., 2005; Thibeault, et al, 2004). The amount of built-in recovery time for teachers was very small as many teachers were lecturing for 5-6 hours daily (Hunter &

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Titze, 2009). Teachers were significantly more likely than other professionals to consider a career change due to voice problems (Roy, et al., 2004). The pervasiveness of vocal symptoms among teachers appears to a growing problem. In a twelve-year period, from 1988-2001, the number of teachers reporting experiencing vocal problems rose considerably. Teachers surveyed who reported experiencing vocal symptoms occurring weekly rose from 12% to 29% in this twelve-year time frame (Simberg, Sala, Vehmas & Laine, 2005). Music teachers were found to be at significantly greater risk of experiencing a voice disorder, while teachers of special and vocational education had a significantly lower risk. Chronic voice disorders were more prevalent among teachers of vocal music and less prevalent among teachers of vocational education (Roy, et al., 2004.) Middle school and high school choral directors were found to be at risk for developing voice problems (Schwartz, 2009). Elementary music teachers experiencing voice problems attributed their problems to high noise levels in the classroom, scheduling demands and numerous responsibilities (Bernsdorf & Burk, 1996). Miller and Verdolini (1995) surveyed private voice teachers (N=125) and a control group of non-singing teachers (N=49) about current vocal problems, defined as a difficulty with voice functioning and found there was not a significant difference in the reporting of current vocal problems. Of the 125 singing teachers surveyed, 21% reported experiencing a current voice problem and 18% of the control group reported a current voice problem.

There was a however,

a significant difference when reporting past vocal problems. Of the singing teachers, 64% reported vocal problems in the past while only 33% of the control subjects reported past problems. Of the teachers who were currently experiencing voice problems, 56% sought

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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medical help while none of the subjects in the control group with voice problems sought medical help. The risk factors for vocal problems were the same for both subject groups. The first factor was the use of drying medications and the second was previous vocal problems. Voice problems appear common among student and new teachers as well, causing many to consider leaving the teaching professions. Hackworth (2009) found that preservice teachers were more likely to consider a career change than teachers with over 11 years of experience. Simberg, Laine, Sala and Ronnemaa (2000) reported that of the 226 preservice teachers surveyed, 20% reported experiencing two or more vocal symptoms occurring weekly. Simberg, Sala and Ronnemaa (2004) compared student teachers (N=175) vocal health to that of other students (N=220). Students answered questions about seven vocal symptoms: throat clearing or coughing, the voice becomes low or hoarse, the voice becomes strained or tires, voice breaks, a sensation of pain or lump in the throat, difficulty in being heard, and loss of voice. The data showed that there was a significant difference in the number of reported vocal symptoms between student teachers (42%) and students in the control group (24%). There is not a conclusive body of research to indicate there is a correlation between number of years in the teaching profession and the frequency of vocal problems (Simberg et al. 2004). In a study by Kooijman, Thomas, Graamans, and de Jong (2007) 1,775 teachers were surveyed about vocal problems with respect to their memories and perceptions of three time periods: their entire career, at the moment, and during the past year. No relationship was found between number of years teaching and the reported development of vocal problems. There were many types of voice problems with symptoms that may include hoarseness, vocal fatigue, breathiness, reduced pitch range, aphonia (absence of voice), pitch breaks, strain, tremor, and pain. (Colton, Casper & Leonard, 2006). The most commonly diagnosed problem in

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teachers appeared to be vocal nodules, caused by intraglottal trauma during voice use. The increase of nodules has been linked to prolonged vocal use, particularly loud voice usage (Brown and Holbrook, 1985). Svec, Popolol and Titze (2003) determined that in order to investigate prolonged voice use, three underlying principles must be explored; (1) duration of voicing; (2) vocal intensity; and (3) fundamental frequency. They adopted the term ‘vocal dose” for measures quantifying the amount of voicing. The simplest measure of vocal dose is the time dose, or voicing dose, which accumulates the total time the vocal folds vibrate during speech and the total number of cycles. Vocal fatigue has often been cited as a vocal health indicator, however establishing a definition and identifying features of vocal fatigue have remained elusive. (Welham and Maclagan, 2003). Although vocal fatigue has been the subject of numerous studies (e.g. Boone, 1988; Colton and Casper, 1996; Burzynski and Titze, 1986; Scherer et al, 1986; and Scherer et al, 1991) it is still not cleat whether there is a definitive link between vocal fatigue and other laryngeal pathologies. Whether vocal fatigue contributes to, results from, or exists independently of other voice conditions is not yet known (Welham and Maclagan, 2003). Titze, Svec and Popolo (2003) refined measure for determining safety standards of vocal dosing. By comparing the limits of exposure to industrial calculations for hand-transmitted vibrations they linked the safety limit (520 m) to the accumulated distance traveled by the vocal folds. With vocal folds traveling about 0.5 m per second, the safety distance of 520 m would be reached after 17 minutes of continuous phonation. The time singers rest during phonation was not taken into account in this calculation, which would provides opportunities to extend a healthy vocal dose longer than 17 minutes.

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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Hunter and Titze (2009) studied vocal loading and recovery times of 72 elementary and secondary teachers. Prior to the project, they were off work for 3 weeks. Data were gathered in three manners: (1) a laryngostroboscopic examination, (2) a variety of vocal health questions and (3) an extensive acoustic analysis Any participants with current voice or speech disorders were screened out by an extensive acoustic analysis. Teachers performed a 2 -hour reading exercise, answering self-administered voice perception questions before, during and after the reading exercise. Hunter and Titze determined that vocal fatigue is a dermal wound, with the healing trajectory similar to a chronic wound healing trajectory rather than an acute wound. Initial healing begins taking place as soon as phonation ceases. The vocal folds are in a constant state of repair, as in a chronic wound. Findings also indicated that within 4-6 hours, 50% recovery had occurred and 90% of recovery occurred within 12-18 hours. Two new tools have been instrumental in providing researchers with data regarding vocal dose and recovery, The Singing Voice Handicap Index and the Ambulatory Phonation Monitor. The Singing Voice Handicap Index (SVHI) was developed to measure self-perceived handicap in singing (Cohen, et al. 2007). The survey was based on the Vocal Handicap Index, using 36 questions gauging the physical, emotional, social and economic impact voice problems have had. It has proven to be a valid and reliable self-measurement tool. The development of the Ambulatory Phonation Monitor (APM) by Titze, Svec, and Popolo (2003), has provided researchers with an additional tool to measure vocal dose. Voice monitoring devices have been employed since 1974 (Cheyne et al). Prior devices used microphones that not only recorded everything being said, but also captured environmental noise, providing less reliable results. Progressing from the earlier Portable Vocal Accumulator,

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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(Cheyne, 2003) the APM was developed as a “vocal accumulator” or “voice dosimeter”. The APM attached miniature accelerometers to the front of the neck to capture vocal vibrations caused by phonation. The APM has allowed researchers to study real time processing of voice data in the actual environment, measuring phonation duration, fundamental frequency, sound pressure levels and vocal dosing. The data collected has been helpful in determining relationships between voice use, vocal fatigue and recovery time and studies have proven the APM to be a reliable instrument (Cheyne, et al, 2003; Szabo et al, 2001, 2003; Hillman, Heaton, Masaki, Zeitels, & Cheyne 2006; and Svec, Popolo, & Titze, 2003). Increased vocal health education has been suggested as a possible way to help teachers combat vocal issues and is a topic that has been researched in conjunction with vocal health (e.g., Chan, 1994; Broaddus-Lawrence, 2000; David, 1996; Kovacic & Budjanovac, 2003; Hackworth 2009). Some research has identified vocal hygiene education for teachers as an effective method to prevent vocal disorders. Chan (1994) researched a population that is at highrisk for voice problems, kindergarten teachers. Kindergarten teachers received a 1.5-hour vocal hygiene workshop. The teachers were given basic information about vocal anatomy and physiology, what constitutes vocal abuse, healthy vocal use and strategies to use in the classroom. Teachers were asked to incorporate their new healthy vocal skills into their daily routines and to keep a daily journal to monitor any vocal abuses or misues. Journal analysis showed that there was a significant reduction in vocal abuses after the vocal hygiene education. However, a more recent study on the effect of vocal hygiene education on vocal habits has not proven a positive connection between the two (Broaddus-Lawrence 2010). Eleven adult singers received 4 hours of instruction on vocal anatomy and physiology, vocally abusive behaviors, voice disorders in singers and measures to prevent voice disorders. The singers

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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completed a survey after their instruction, which indicated that they had a better understanding of their vocal instrument, valued the information they had learned and would recommend it to fellow singers. However, there was no significant reduction in vocally abusive behaviors. There were some minor decreases in the quantity of abusive behaviors such as clearing the throat, yelling and alcohol consumption. While there has been a great deal of research compiled regarding occupational voice disorders in the teaching and music teaching professions, there has been comparatively a small amount regarding vocal complaints among students, particularly adolescents. Voice changes during puberty are well documented (Cooksey, 2000; Gackle, 2000) yet there still remains limited research on adolescent voice use and recovery. Four studies to date have investigated adolescent voice use. Schloneger (2009) used the Ambulatory Phonation Monitor (APM) to study voice use of two undergraduate singers before, during and after an intense week of choral and musical theatre rehearsals. Data were acquired from participants (N=2) through (a) APM data; (b) participant activity logs; (c) daily surveys; (d) administration of the Singing Voice Handicap Index (SVHI); and (e) the Keirsey Temperament Sorter. APM data results showed an increase of time dose percentages for both participants during the intense rehearsal week. One student showed an increase of 11.59% (from 6.94 % to 18.53%) and the other student evidenced a 2.9% increase from pre-test to during the week. Declines were evidenced in 6 of the 9 areas in the vocal health surveys between Monday and Friday of the intensive week. Relationships between personality profiles, voice use and perceptions of fatigue were explored with the assistance of the Keirsey Temperament Sorter. One female participant (A) was identified as an introvert and the other

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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subject (B) as an extrovert. Participant A experienced an increase in perceived voice handicap during the intensive rehearsal week while Participant B perceived less voice handicap Sataloff (2002) administered a closed set questionnaire to 129 adolescent choral singers in the Delaware area. Of those responding, 55.8% reported they had experienced vocal difficulty. They reported experiencing vocal difficulties in the following areas: hoarseness (42.6%), fatigue (24%), change in voice range (19.4%), tickling or choking sensation (17%), volume disturbance (16.3%), breathiness (15.5%), prolonged warm-up (6.2%) and other (12.4%). Almost one-third of the singers (31%) felt they were “oversinging” and 43% felt they had to strain their voices during choral rehearsals. Data were disaggregated by those who had taken lessons and those who had not with no significant differences indicated. Female singers who had taken lessons and had reached puberty displayed an increase of voice difficulties but the same did not hold true for male singers taking lessons who had reached puberty. Adolescent student vocal use and perceived vocal health were studied during a three-day Midwest all-state choir experience (Daugherty, Manternach, & Price, in press). Data were accumulated from four perspectives: (a) daily student surveys of vocal health and perceived singing quality plus self-reported sleep hours; (b) Vocal dose data (Dt) from two students, one female and one male, wearing APM monitors during much of the event; (c) rehearsal recording analysis; and (d) field notes. Comparisons of the first and final day surveys indicated significant deterioration in student self-perception of singing voice quality and found students reporting noteworthy changes in 5 of 7 vocal health indicators surveyed: tired voice, hoarseness, comfortable access to higher range, strained singing and throat pain. Although the students selfreported sleep hours decreased significantly, 78.8% of the participants felt they had taken good care of their voices.

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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Data from the two students wearing the Ambulatory Phonation Monitors provided a basis for study and future research. There was little variance in percentages of vocal fold contact time between rehearsal and non-rehearsal events. Vocal health among high school students in fulltime residence at a summer choral camp has been examined by Bowers and Daugherty (2008). Participants (N=114) were surveyed pre and post - camp to document any self- perceived vocal production changes. Twelve areas were addressed in the survey. Six of them, use of voice in high and low ranges, dynamic control, excessive throat clearing and self assessment of how well each had taken care of their voice throughout the week, did not change significantly from pre and post camp surveys. The six areas that did show significant change were hoarseness, vocal fatigue, dryness, throat pain, straining to sing and effort to sing/breathiness. Although many reported increased vocal fatigue and strain, the participants reported that they had taken good care of their voices. No research to date has used voice dosimetry to gather phonation data from adolescents during a choral camp experience. The purpose of this case study was to document adolescent voice use during a five day mornings only choral music camp experience through (a) daily surveys of participants (N= 25) soliciting responses to seven voice health indicator statements and number of sleep hours, (b) acquisition of phonation time dose (Dt) and phonation distance dose (Dd) data from two female students who wore ambulatory phonation monitors (APMs) during waking hours each day during camp week and for two baseline periods (two days prior to camp and one day following camp), and (c) three administrations of the Singing Voice Handicap Index (SVHI) to the two students wearing the APMs. The following research questions were the basis for this study: 1. What do perceptual measurements (vocal health/ perceived singing voice

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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quality questionnaires) indicate about participants’ perceptions of vocal health and vocal quality during the time periods of interest? 2. What do ambulatory phonation monitor data acquired from two adolescent female singers indicate about phonation duration, frequency and amplitude during choir camp, including overall phonation time and phonation periods disaggregated by rehearsal vs. non-rehearsal events? Definitions Phonation is the production of sound as caused by the vocal folds adducting in mutual vibration. Phonation time dose Dt) refers to the cumulative duration of time (hh:mm:ss) the vocal folds have actually touched in a given time frame. Fundamental frequency (Fo) describes the rate at which the vocal folds vibrate and is perceived as “pitch”. A vibratory cycle is one complete round-trip of opening and closing of the vocal folds. Vocal dose refers to the accumulated number of repetitive cycles in a particular time period. Distance Dose (Dd) is an estimated measure of the “distance” traveled by the vocal folds. Methods and Procedures Participants and Camp Schedule Participants (N=25: 16 females and 9 males) were adolescent singers attending a Midwestern Catholic High School Choir Camp open to members of that school’s choir program. All were members of that school’s top choral ensemble (Chamber Singers), and had been selected by audition process. All of the females (N=16) were also members of the top all female ensemble (Honors Choir). The females rehearsed as members of both Honors Choir (8 a.m.-10 a.m.) and Chamber Singers (10 a.m.-noon) while the males only rehearsed with Chamber Singers

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from 10 a.m.-noon. Participants ranged in age from 15 to 17 years, with a modal age of 16. The camp was designed to build camaraderie among choir members and to prepare music for the upcoming school year. In this regard, the final camp day was a day-long event (7 hours) with various team-building activities and no rehearsals. Two adolescent female singers (pseudonyms Alissa and Maggie) wore ambulatory phonation monitors (APM, KayPentax Model 3200) during the time period studied. Alissa was chosen to wear the APM because she was involved in Chamber Singers Camp (hereafter referred to as CS), and Opera Camp (hereafter referred to as OC). Maggie was chosen to wear the APM because she was involved in both CS and Honors Choir Camp (hereafter referred to as HCC). Alissa, aged 17, was a junior in high school and sang primarily the scored soprano I parts. She was beginning her third year in the choir program and had been in Honors Choir three years and in Chamber Singers for two years. Alissa had been singing in school choirs since she was 10 years old and had been involved in youth musical productions and youth opera camp and productions. She had taken private voice lessons for three years. Alissa plans to major in vocal performance in college. She was in Stage III of the Gackle stages of adolescent development and is post-menarcheal. Alissa was participating in a community opera camp at the same time of the high school camp. She attended the high school camp from 8-10 a.m. and the opera camp from 11 a.m.-4 p.m. The number of hours she was participating in singing activities was one of the reasons she was chosen to wear the APM. Maggie, 15, was a high school sophomore and a soprano. She was beginning her second year in the choir program and her first year in Honors Choir and Chamber Singers. Maggie also sings in an outside choir throughout the school year and does not take private voice lessons. She is in Stage III of the Gackle stages of female adolescent development and is post-menarcheal.

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The choir camp met for five consecutive days (Monday – Friday). Honors Choir, an all female ensemble rehearsed from 8 a.m.-10 a.m. and Chamber Singers, a co-ed ensemble rehearsed from 10 a.m. -12 p.m. Honors Choir members were given a 15-minute break from 10 a.m.- 10: 15 a.m. Survey Instrument Participants completed a daily survey, which was researcher-designed and based on a previous research study by Daugherty, Manternach and Price (2009). The survey was administered at the start of the first camp day and at the conclusion of the camp day for the remainder of the week. The survey was in two parts and consisted of a demographic section detailing age, voice part sung and vocal hygiene questions. The second part asked students to respond to seven statements, addressing seven of the nine symptoms identified by Colton, et al. (2006) as contributing to voice problems. They were: (a) inability to access higher notes of the voice range, (b) frequent throat clearing, (c) sense of breathiness in vocal sounds, (d) strain, (e) tiredness, (f) throat pain, and (g) hoarseness. These statements were drawn from prior investigations (e.g. Daugherty, Manternach and Price 2009, Bowers & Daugherty, 2008; Deutsch, et al., 2002; Tavares & Martins, 2007). Students used a five-point scale to rate their perceived singing quality from “very poor” to “excellent.” The two students who wore the APMs were administered the Singing Voice Handicap Index (SVHI) (Cohen, et al., 2007) on the first pre-camp baseline day at the start of the day, on day four of the camp prior to the first rehearsal and for a third time on the post-camp day at the beginning of the day. The two students wearing the APMs wore them for two days prior to the camp to establish a baseline, for the five camp days, and for one day immediately following the camp (Post Baseline).

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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Phonation Monitors The APM was comprised of a small accelerometer transducer that attaches to the anterior base of the neck, above the sternal notch via adhesive and a battery-powered microprocessor unit worn in a pack at the waist. The accelerometer captured phonation vibrations and raw data at a rate of 20 samples per second, conveying the information to the microprocessor. This information was daily downloaded onto a computer where it was store and calculated. Mean phonation duration, percentage of phonation time, fundamental frequency, and voice amplitude levels were all measured. The participants met the researcher every morning before camp to calibrate the monitors and download the previous day’s data. The participants wore the monitors for 12-15 hours each day, beginning shortly before 8 am. Results The results are reported in order of the research questions posed for this study. To answer these questions, two types of data were utilized and analyzed: (a) survey and (b) ambulatory phonation monitor. Research Question One: Daily Vocal Health Survey Data The response rates for the survey were as follows: Monday (N=25, 100%), Tuesday (N=25, 100%), Wednesday, N=24, 96%) Thursday, N=25, 100%) and Friday (N=25, 100%). Vocal Health Indicator Statements Tables one and two compare the first day (Monday) and the fourth day (Thursday) with participants disaggregated by sex. Males participated in the camp for two hours each day Monday through Thursday, while females were in camp for four hours on each of those days. For the females, there were no significant differences between Monday and Thursday. For the

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males, the only significant difference was in question 5 today, my voice feels tired. They reported less vocal fatigue on Thursday than on Monday. Table 1 Monday / Thursday Comparisons of Self-Reported Vocal Health Indicators- Males Statement 1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired. 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

Monday Mean Rank Scores 07.8

Thursday Mean Rank Scores 11.2

z score

p

-1.28

.200

11.4

07.6

01.46

.144

09.2

09.8

-0.22

.826

10.6

08.4

00.79

.429

12.7 10.1 10.0 07.6

06.3 08.9 09.0 11.4

02.47 00.42 00.35 -1.46

.013* .689 .726 .144

Table 2 Monday / Thursday Comparisons of Self-Reported Vocal Health Indicators- Females STATEMENT Monday Thursday z Mean Rank Mean Rank score Scores Scores 1. Today, I can comfortably sing the higher 15.1 17.9 -0.85 notes of my voice range 2. Today, I find myself clearing my throat 18.2 14.8 0.98 more than I typically do. 3. Today, I sense airiness/breathiness in the 15.8 17.2 -0.38 sound of my voice. 4. Today, I feel like I’m straining when I sing. 18.0 15.0 0.87 5. Today, my voice feels tired. 17.0 16.0 0.26 6. Today, my throat hurts when I sing. 15.1 17.9 -0.85 7.Today, my voice is hoarse. 16.2 16.8 0.44 8. The quality of my voice today is 13.3 19.8 -1.94

p

.395 .327 .703 .384 .794 .395 .882 .052

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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Tables three and four compare Monday and Friday, (off-site team building day) with participants disaggregated by sex. No significant differences were found. Table 3 Monday / Friday Comparisons of Self-Reported Vocal Health Indicators- Males Statement 1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired. 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

Monday Mean Rank Scores 9.5

Friday z score Mean Rank Scores 9.5 0.04

p 0.968

11.2

7.8

1.32

0.186

9.2

9.8

-0.22

0.826

10.8

8.2

0.97

0.332

12.5 10.1 10.2 7.6

6.5 8.9 8.8 11.4

2.34 0.40 0.53 -1.46

0.019 0.689 0.596 0.144

Table 4 Monday / Friday Comparisons of Self-Reported Vocal Health Indicators- Females Statement Monday Friday z score Mean Rank Mean Rank Scores Scores 1. Today, I can comfortably sing the higher 16.8 16.2 0.19 notes of my voice range 2. Today, I find myself clearing my throat 17.3 15.8 0.43 more than I typically do. 3. Today, I sense airiness/breathiness in the 13.9 19.1 -1.56 sound of my voice. 4. Today, I feel like I’m straining when I 17.6 15.4 0.66 sing. 5. Today, my voice feels tired. 17.7 15.3 0.72 6. Today, my throat hurts when I sing. 15.9 17.1 -0.34 7.Today, my voice is hoarse. 16.7 16.3 0.09 8. The quality of my voice today is 13.4 19.6 -1.87

p 0.849 0.667 0.119 0.509 0.471 0.734 0.928 0.061

Table 5 compares male and female self-reported vocal health indicators of the first day,

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Monday. No significant difference was found based on participants’ sex. Comparison was also made between male and female participants on the 4th day of camp, Table 6 and the 5th day of camp, Table 7. No significant differences were found on day 4, Thursday or on day 5, Friday. Table 5 Monday Male / Female Comparisons of Self-Reported Vocal Health Indicators Statement

Male Mean Rank Scores

1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired. 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

z score

p

14.3

Female Mean Rank Scores 12.3

0.62

.535

14.3

12.3

0.65

.516

12.8

13.1

-0.08

.936

10.8 12.7 12.1 12.8 13.2

14.3 13.2 13.5 13.1 12.9

-1.10 -0.14 -0.42 -0.06 0.06

.271 .889 .674 .952 .952

Table 6 Thursday Male / Female Comparisons of Self-Reported Vocal Health Indicators STATEMENT

1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired. 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

Male Mean Rank Scores 15.5

Female Mean Rank Scores 11.6

z score

p

01.25

.211

12.1

13.5

80.52

.653

12.7

13.2

-0.11

.912

10.4 09.1 09.0 13.8 15.2

14.5 15.2 15.3 12.5 11.8

-1.33 -1.98 -2.01 00.44 01.08

.193 .048 .044 .689 .280

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Table 7 Friday Male / Female Comparisons of Self-Reported Vocal Health Indicators STATEMENT 1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired. 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

Male Mean Female z Rank Scores Mean Rank score Scores 14.3 12.3 0.62

p 0.533

12.6

13.2

-0.17

0.865

10.7

14.3

-1.16

0.246

09.5 09.9 10.3 11.6 13.3

15.0 14.8 14.5 13.8 12.8

-1.76 -1.56 -1.33 -0.68 0.11

0.078 0.119 0.183 0.497 0.912

Table eight compares Monday (first day prior to rehearsal) and Thursday (final day of actual singing at the end of the rehearsal) survey data among all participants. Table nine compares Monday (first day prior to rehearsal) and Friday (off-site team building day) survey data. Only one statement, quality of my voice today, showed a significant difference, with students ranking their vocal quality better on Thursday and Friday than Monday. Table 8 Monday / Thursday Comparisons of Self-Reported Vocal Health Indicators Statement 1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired.

Mean Rank Scores for Mon 22.5

Mean Rank Scores for Thurs

z score

p

28.5

-1.43

.153

28.6

22.4

1.48

.139

24.6

26.4

-0.44

.660

27.9

23.1

1.16

.246

28.8

22.2

1.59

.112

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

24.9 25.7 20.4

26.1 25.3 30.6

20 -0.27 0.09 -2.47

.787 .928 .014*

Table 9 Monday / Friday Comparisons of Self-Reported Vocal Health Indicators Statement 1. Today, I can comfortably sing the higher notes of my voice range 2. Today, I find myself clearing my throat more than I typically do. 3. Today, I sense airiness/breathiness in the sound of my voice. 4. Today, I feel like I’m straining when I sing. 5. Today, my voice feels tired. 6. Today, my throat hurts when I sing. 7.Today, my voice is hoarse. 8. The quality of my voice today is

Mean Rank Scores for Mon. 24.7

Mean Rank Scores for Fri. 26.3

z score

p

-0.4

0.689

28.3

22.7

1.36

0.173

23.1

27.9

-1.15

0.250

27.7

23.3

1.07

0.285

29.4 26.1 26.4 20.5

21.6 24.9 24.6 30.5

1.90 0.29 0.43 -2.44

0.057 0.771 0.667 0.015*

Using the same eight vocal health indicator statements, comparison was made between each day of camp, Monday / Tuesday, Tuesday/ Wednesday, Wednesday / Thursday, and Thursday/Friday. The only significant decline was from Monday to Tuesday among all participants on question 2: I find myself clearing my throat more than I typically do, U(25, 25) = 274.5, p = .047, two-tailed. Sleep Hours Students’ sleep hours were reported on the survey starting with the Sunday prior to the first day of camp through Thursday. Table 10 shows the mean and mode numbers of self-reported sleep hours for all camp participants. Table 11 disaggregates the mean and mode numbers of self-reported sleep hours by male and female participants. Both male and female participants experienced a slight increase in the amount of sleep from the beginning to the end of the week of

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camp. Table 10 Self-Reported Sleep Hours for all Participants Day Sunday Monday Tuesday Wednesday Thursday

Mean Sleep Hours 6.81 6.66 7.16 7.64 7.38

Modal Sleep Hours 7 7 8 8 7

Table 11 Self-Reported Sleep Hours Disaggregated by Male and Female Participants Day Sunday Monday Tuesday Wednesday Thursday

Male Mean Sleep Hours 6.72 6.38 7.5 7.39 7.39

Male Modal Sleep Hours 7 7 8 5 8

Female Mean Sleep Hours 6.86 6.81 6.97 7.78 7.37

Female Modal Sleep Hours 7 6 8 8 7

Table 12 Male / Female Comparisons of Self-Reported Sleep Hours

Sunday Monday Tuesday Wednesday Thursday

Male Mean Rank Scores

Female Mean Rank Scores

12.4 12.8 14.4 12.6 14.1

13.3 13.1 12.2 13.3 12.4

z score -0.25 -0.06 0.68 -0.20 0.51

p score 0.803 0.952 0.497 0.841 0.610

Table 12 analyzes self-reported sleep hours disaggregated by male and female participants. There was not a significant difference between male and female participants. Student self-reported sleep hours were compared Sunday to Monday, U (25, 25) = 311.5, p =

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0.992, two-tailed; Monday to Tuesday, U (25, 25) = 375, p = 0.23, two-tailed; Tuesday to Wednesday, U (25, 25) = 361, p = 0.352, two-tailed; and Wednesday to Thursday, U (25,25) = 269.5, p = 0.412, two-tailed. No significant difference was found. Sleep hours from Sunday (night prior to camp day one) and Wednesday (night prior to final singing day of camp) were also analyzed with no significant difference found, U (25,25) = 419, p = 0.039, two-tailed. SVHI Results Alissa and Maggie both scored within normal parameters in each of three administrations of the SHVI. Both participants reported scores of “never” or “almost never” in response to each item on this index. Research Question 2: Phonation Monitor Data Tables 13 and 14 present overall phonation data for Alissa and Maggie disaggregated by camp week and pre/post test days. Table 13 Overall Phonation Duration Data for Alissa Alissa

APM Duration

Phonation Time

Phonation % (Dt)

Pre-Camp Day 1 Pre-Camp Day 2 Camp Day 1 Camp Day 2 Camp Day 3 Camp Day 4 Camp Day 5 –Field Trip Post Camp Total Baseline Days

12:15:08

02:18:33

14:23:34

Cycle Dose

18.85%

M Amplitude dB 74.66

2,476,304

Distance Dose(Dd) -m 5670.41

Fo Mode Hz 207.00

Fo Means Hz 298.18

01:25:52

9.94%

65.26

1,571,687

2842.93

229.00

305.05

15:25:48

01:34:08

10.17%

75.50

1,862,492

4601.44

229.00

329.80

14:58:34

01:04:37

7.19%

64.25

1,286,484

2198.79

339.00

331.79

15:48:56

02:13:18

14.05%

74.69

2,553,648

6720.24

229.00

319.55

12:49:47

01:57:13

15.23%

82.80

2,322,898

8045.12

229.00

330.29

14:18:45

01:48:16

12.61%

82.41

1,538,840

5067.28

229.00

318.98

21:50:04 48:28:46

00:44:38 04:29:03

03.41% 10.73%*

94.66 78.193*

702,088 1,583,360*

4759.54 4424.29*

207.00 214.33*

262.12 288.45*

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION Total Camp Days Overall Total

23

73:21:50

08:37:32

11.85%*

75.93 *

1,912,870*

5326.57*

251.00*

326.08*

121:50:36

13:06:35

11.43%*

76.78 *

1,789,30*

4988.22*

237.25*

311.97*

Cycle Dose

Fo Mode Hz 229

Fo Means Hz 286.80

* = means

Table 14 Overall Phonation Duration Data for Maggie Maggie

APM Duration

Phonation Time

Pre-Camp Day 1 Pre-Camp Day 2 Camp Day 1 Camp Day 2 Camp Day 3 Camp Day 4 Camp Day 5-Field Trip Post Camp

11:10:40

1:50:24

12:30:16

Total Baseline Days Total Camp Days Overall Total

Phonation % (Dt) 16.46%

M Amplitude dB 72.40

1,893,249

Distance Dose-(Dd) m 3841.78

1:38:30

13.13%

71.31

1,653,967

3474.19

229

280.04

12:15:05

2:02:53

16.72%

74.52

2,369,086

5701.81

229

321.48

13:45:34

2:33:40

18.61%

64.25

1,286,484

2198.79

229

309.55

15:48:56

2:46:44

20.95%

74.34

3,236,993

7646.24

229

323.91

14:20:26

2:51:13

19.90%

82.53

3,358,898

10,923.40

229

327.35

13:14:25

1:28:19

11.12%

73.51

1,549,705

4202.12

229

229.55

11:57:50

1:32:56

12.95%

94.66

1,893,249

4759.54

229

277.39

35:38:46

5:01:50

10.73%*

72.70*

1,583,360*

3839.36*

69:24:48

11:42:49

11.85%*

73.83*

2,360,233*

6087.78*

229* 229*

302.37*

105:03:34

16:44:39

11.43%*

73.40*

1,813,488*

5244.63*

229*

294.51*

281.41*

Note: * = means

Tables 15-19 present Alissa’s APM data for all five camp days in descending order of phonation time percentages disaggregated by Honors Choir Camp, Opera Camp, camp nonrehearsal time, and non-camp time. In four out of five of the days, her highest phonation percentages were during Honors Choir Camp. On camp day two, Alissa’s highest phonation percentage was during camp non-rehearsal time. In three of the four days, her amplitude averages for Opera Camp were the highest while her phonation percentages for Opera Camp

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24

were either third or fourth. Alissa stated that she was in a large chorus and there was a great deal of standing around waiting to sing. Table 15 Alissa Camp Field Trip APM Data in Descending Order of Phonation Time Percentages Camp Day Five

APM Duration

Phonation Time

Phonation %

Non Camp

07:18:45

00:54:33

12.99%

M Amplitude dB 77.49

Off Site Field Trip Camp

07:00:00

00:52:29

12.50%

84.80

Cycle Dose

Distance Dose-m

F0 Mode Hz

933,144

2641.46

229

Fo Means Hz 285.08

1,093,715

3740.57

383

347.29

Table 16 Alissa Camp Day One APM Data in Descending Order of Phonation Time Percentages Camp Day One

APM Duration

Phonation Time

HCC*

02:00:00

00:21:00

Camp Non Rehearsal OC*

01:00:00 05:40:00

Phonation % (Dt)

Cycle Dose

Distance Dose-m

Fo Mode Hz

17.5 %

M Amplitude dB 79.28

473,587

1183.77

339

Fo Means Hz 376.06

00:18:58

15.81%

77.62

399,776

963.41

339

351.33

00:26:55

8.98%

80.34

549,175

1566.75

383

305.05

67.96

303,207

552.74

229

294.71

Non06:45:48 00:17:08 7.14% Camp Note: HCC = Honors Choir Camp, OC = Opera Camp

Table 17 Alissa Camp Day Two APM Data in Descending Order of Phonation Time Percentages Camp Day Two

APM Duration

Phonation Time

Phonation %

Camp Non -Rehearsal HCC*

01:00:00

00:10:52

18.13%

M Amplitude dB 67.21

02:00:00

00:21:39

18.05%

OC*

05:30:00

00:27:51

9.28%

Non06:28:34 00:04:13 0.17% Camp Note: HCC = Honors Choir Camp, OC = Opera Camp

Table 18

Cycle Dose

Distance Dose-m

Fo Mode Hz

198,399

390.43

273

Fo Means Hz 303.99

58.23

425,868

567.44

339

327.65

67.88

587,505

1117.76

383

351.58

64.58

74,712

123.26

273

294.26

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

25

Alissa Camp Day Three APM Data in Descending Order of Phonation Time Percentages Camp Day Three

APM Duration

Phonation Time

Phonation %

Cycle Dose

23.80%

M Amplitude dB 65.52

HC*

02:00:00

00:28:33

Camp Non -Rehearsal NonCamp OC*

01:00:00

Distance Dose-m

Fo Mode Hz

597,469

945.53

339

Fo Means Hz 348.85

00:11:52

19.79%

73.26

228,728

527.92

273

321.00

07:30:00

00:59:52

12.77%

77.68

1,151,248

3465.99

229

320.60

04:30:00

00:33:00

11.00%

77.79

576,203

1780.90

229

291.79

Note: HCC = Honors Choir Camp, OC = Opera Camp

Table 19 Alissa Camp Day Four APM Data in Descending Order of Phonation Time Percentages Camp Day Four

APM Duration

Phonation Time

Phonation %

HC*

02:00:00

00:29:07

24.27%

Non05:00:00 00:48:30 16.74% Camp OC* 04:30:00 00:34:21 11.45% Camp Non 01:00:00 00:06:07 10.22% -Rehearsal Note: HCC = Honors Choir Camp, OC = Opera Camp

M Amplitude dB 77.99

Cycle Dose

Distance Dose-m

Fo Mode Hz

684,415

1593.64

383

Fo Means Hz 391.70

83.34

860,847

3285.83

229

295.87

86.01 86.17

685,488 107,769

2811.62 451.76

338 229

332.53 292.85

Tables 20-24 present Maggie’s APM data in descending order of phonation time percentages for the four camp days and the one off-site camp day. Maggie’s greatest percentages of phonation were during Honors Choir Camp or Chamber Singers. On the off-site camp day, Maggie had a higher phonation percentage during non-camp time. Table 20 Maggie Camp Field Trip APM Data in Descending Order of Phonation Time Percentages Camp Day Five

APM Duration

Phonation Time

Phonation %

Non Camp

06:14:25

00:44:10

11.80%

M Amplitude dB 72.02

Off Site Field Trip Camp

07:00:00

00:44:09

10.51%

75.01

Cycle Dose

Distance Dose-m

Fo Mode Hz

735,157

1742.14

229

Fo Means Hz 277.41

814,548

2226.57

229

307.68

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

26

Table 21 Maggie Camp Day One APM Data in Descending Order of Phonation Time Percentages Camp Day One

APM Duration

Phonation Time

Phonation %

HCC*

02:00:00

00:28:42

23.92%

M Amplitude dB 74.06

Non08:18:05 01:12:41 15.14% Camp CS 00:45:00 00:06:41 14.86% *Sectional CS* 01:00:00 00:06:04 10.12% Camp 00:15:00 00:00:15 1.71% NonRehearsal Note: HCC = Honors Choir Camp, CS = Chamber Singers

Cycle Dose

Distance Dose-m

Fo Mode Hz

623,807

1343.77

339

Fo Means Hz 362.47

75.54

1,270,161

3422.16

229

291.40

73.59

133,087

319.07

229

331.80

72.23 66.80

94,539 4,959

234.79 9.65

229 229

259.51 325.25

Table 22 Maggie Camp Day Two APM Data in Descending Order of Phonation Time Percentages Camp Day Two

APM Duration

Phonation Time

Phonation %

CS*

01:00:00

00:12:51

21.44%

M Amplitude dB 75.34

HC* 02:00:00 00:32:00 21.33% Non09:15:34 01:46:54 18.26% Camp CS* 01:00:00 00:07:39 17.02% Sectional Camp 00:15:00 00:00:36 4.08% NonRehearsal Note: HCC = Honors Choir Camp, CS = Chamber Singers

Cycle Dose

Distance Dose-m

Fo Mode Hz

284,863

693.48

229

Fo Means Hz 369.44

78.25 82.11

658,775 1,888,672

1887.26 6975.57

339 229

343.40 294.71

77.97

151,058

441.80

339

328.82

76.49

11,196

36.35

251

304.64

Table 23 Maggie Camp Day Three APM Data in Descending Order of Phonation Time Percentages Camp Day Three CS*

APM Duration 01:00:00

Phonation Time

Phonation %

00:17:22

28.96%

M Amplitude dB 77.12

HCC* 02:00:00 00:34:27 24.62% CS* 00:45:00 00:10:21 23.03% Sectional Non9:15:53 01:50:17 19.84% Camp Camp 00:15:00 00:01:59 13.31% NonRehearsal Note: HCC = Honors Choir Camp, CS = Chamber Singers

Cycle Dose

Distance Dose-m

Fo Mode Hz

394,782

899.68

449

Fo Means Hz 278.67

75.98 75.15

777,375 209,608

1768.68 484.29

339 339

375.96 337.37

73.77

2,004,643

4,881.68

229

303.42

74.10

36,914

72.17

229

308.54

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Table 24 Maggie Camp Day Four APM Data in Descending Order of Phonation Time Percentages Camp Day Four

APM Duration

CS*

01:00:00

Phonation Time 00:16:56

Phonation % 28.23%

M Amplitude dB 82.87

HC* 02:00:00 00:26:18 21.93% Non10:20:26 01:58:02 19.03% Camp CS* 00:45:00 00:07:50 17.43% Sectional Camp 00:15:00 00:02:09 14.34% NonRehearsal Note: HCC = Honors Choir Camp, CS = Chamber Singers

Cycle Dose

Distance Dose-m

Fo Mode Hz

406,969

1131.27

449

Fo Means Hz 400.59

80.37 82.95

638,202 2,099,121

1599.13 7477.58

383 229

404.51 296.71

82.02

171,852

548.34

449

366.7

82.70

44,025

149.56

229

341.41

APM Participants Written Comments Alissa, the participant involved in both the school and opera camps indicated that her voice was getting hoarse and tired throughout the week. Results from her vocal health questionnaire indicated perceived increased vocal fatigue. Her mid-week comments included “I’m tired and having problems with my voice”, “ I feel like I’m singing like a man”, and “my voice seems to be getting lower and lower”. Maggie reported a much less hectic week, singing only at the choir camp with non-camp time afterwards. She did not indicate any perceived increase in vocal fatigue through her SVHI or daily survey. Her comments midweek included “I feel like I was rusty at the beginning of the week but am starting to sing stronger now” and “I hadn’t been singing much over the summer so at the start of the week, it was harder. Now, I feel like I’m getting back into shape”. Discussion This study explores student voice use and perceptions of vocal health during a five-day school-based choir camp that met for 2 – 4 hours each day. Findings suggest two areas that emerge as topics for further research by vocal music educators: (a) length of music camps in

Running head: ADOLESCENTS’ VOICE USE AND PERCEPTION

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relation to vocal health and (b) number of sleep hours in relation to perceived vocal health. In addition, this study provided more data regarding adolescent voice care using Ambulatory Phonation Monitors. There is still a scarcity of APM data and this study adds to that body of literature. A previous camp study investigated adolescent voice use at overnight camps where students were engaged in singing 6-8 hours / day in addition to other, onsite activities from breakfast to bedtime. In addition, the end result of that camp was to present a final concert. In this study, the camp was much shorter, ranging from 2-4 hours / day on site, with students remaining in their homes for sleep. The outcome of this camp was not to present a concert at the conclusion of the camp thereby relieving students of that pressure. In addition, the camp director had some training in voice care and presented daily brief segments regarding voice use to the camp participants. The students actually ranked their perceived quality of voice higher on Thursday than at the start of camp on Monday. That perception may have been due to the fact that the camp was in August and most of the participants had not been singing in an organized ensemble since the preceding May. When comparing male / female self-reported health indicators for Thursday, there was very little perceived vocal deterioration on day four of the camp for male participants who were in the camp for two hours / day or for the female participants, who were in camp for a total of four hours. Further research using APM data would prove beneficial in determining appropriate rehearsal times for adolescent singers. It would seem therefore that two to four hours of scheduled rehearsal time per day in a summer camp experience did not, for these particular participants, occasion as significant, declining changes in responses to voice health indicator statement, as occurred with adolescent participants in two other studies (Bowers & Daugherty, Daugherty, Manternach & Price) where

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students were scheduled to be on site for each of 3-5 full days, which included a heavier schedule of rehearsal, instructional, and group non-singing activities. In this study and the two mentioned above, it appears that an early indicator of vocal fatigue may be students’ perception of “tired voice”. Further research might explore connections between adolescents’ perception of a tired voice, physical fatigue and sleep hours. Lack of sleep has been linked to poor vocal health in previous studies. The fact that this camp was not an overnight experience may have contributed greatly to the fact that the participants did not feel as though their voices were deteriorating throughout the week. In the camp study done by Bowers and Daugherty, (2008) lack of sleep was seen as a contributing factor to self-perceived vocal problems. This data may foster further research into adolescent sleeping hours and vocal health. A major contribution of this study is the amount of phonation data collected from adolescent females. The APM units were worn for 16 complete days, from 12-15 hours per day. To date, phonation data reported from adolescent females across a period of time continues to be a lacuna in the research literature. As with any new device, there are still some difficulties that need to be addressed. Both girls experienced an irritation at the location of the transducer. Both participants were extremely fair-skinned which may have been a contributing factor. For a week after the study, they had a red circle on their sternal notch. Additional APM data will continue to assist vocal researchers in understanding vocal care for students.

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