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Mapping of Vocal Risk in Amateur Choir
Milka Rosa and Mara Behlau, São Paulo, Brazil
Summary: Objectives. The study aimed to investigate and map the existence of vocal risk in amateur singers, ana-
lyzing the contribution of general voice signs and symptoms, specific singing handicap, and generalized anxiety.
Study Design. This is a cross-sectional study.
Methods. The sample comprised 526 volunteer amateur choristers—186 male and 340 female—(mean age of 42.07
years) from different choirs in the region of São Paulo. Three questionnaires were used: the Voice Symptom Scale (VoiSS),
the Modern Singing Handicap Index (MSHI), and the Generalized Anxiety Disorder 7-item (GAD-7) scale.
Results. The mean total score obtained on the VoiSS was 17.57, which is almost two points higher than the prot-
ocol’s passing score (16). The choristers who scored higher or equal to 16 points (51.5%, n =271)—considered at vocal
risk—and the group who scored less than 16 points (48.5%, n =255)—healthy group—were analyzed separately. The
risk group presented a mean total score of 26.34 on the VoiSS and 20.97 on the MSHI, with higher deviation on the
impairment subscale, followed by the disability and handicap subscales, along with mild anxiety. The healthy group
presented a mean total score of 8.27 on the VoiSS and 6.11 on the MSHI, also with higher deviation in the impairment
subscale, followed by disability and handicap, and a minimum level of anxiety.
Conclusion. Even in leisure activities, vocal care is necessary for the correct use of the singing voice, which demands
individual adaptations. The use of protocols for voice symptoms and singing handicap has revealed the possibility of
amateur choristers to present vocal risk.
Key Words: voice–dysphonia–singing–quality of life–self-assessment.
INTRODUCTION
There are many amateur choirs that are affiliated to schools, re-
ligious groups, communities, or other organizations that develop
this activity for self-gratification.1The choir singing practice is
used as a tool for motivation and social integration,2contribut-
ing for personal development, increasing self-esteem, and
preserving emotional balance.3Some authors4have mentioned
that this activity therapeutically relieves tension and sadness of
daily life. They also report the importance of music for the
elderly.5
Developing a healthy vocal singing technique in the choir is
essential for singing.1Vocal misuse and abuse may cause some
voice disorders.6In amateur choirs, the singers are not techni-
cally trained musicians; thus, they do not have the necessary skills
to consistently and reliably produce the sounds requested by the
conductors while avoiding vocal injuries.1In these choirs, the
conductor is usually the only member with musical training. Many
choristers make rehearsals their only source of knowledge on
vocal techniques.1
The socialization provided by singing in a choir has broad-
ened the objectives of learning how to sing to a point where today
there are actually more lay than professional choirs. This brings
the layperson closer to musical achievement, but on the other
hand one should take vocal care into consideration in order to
avoid risks.7Risk may be defined as the likelihood of a disease
in a population or group for a period of time, that is, the pos-
sibility of acquiring a voice disorder, in our case related to singing
activities and/or other situations of vocal use.8
Teachers and singers are professionals who present higher fre-
quency of voice disorders than the general population,9and
functional dysphonia is the most frequent diagnosis10 among voice
professionals. It is even less frequent among amateur choris-
ters, who sing in choirs as a hobby. These choristers are rarely
submitted to vocal screening. They may not receive education
on proper voice use for speaking or for singing.11 Because of a
lack of specific preparation, amateur choristers may present symp-
toms that may lead to a vocal handicap. Less experienced singers
may be at a greater risk than professional singers.12 In other words,
the greater the singer’s experience, the lower the potential of a
vocal handicap.13
In a Swedish14 and an American15 study, the subjects with higher
vocal risk are singers, followed by consultants, teachers, lawyers,
pastors, telemarketing operators, salesmen, and health profes-
sionals. Singers present high prevalence of abnormal findings
on videolaryngostroboscopy examinations, ranging from reflux
to lesions caused by vocal abuse and tension on the vocal folds.16
It is known that voice professionals have higher occurrence of
vocal problems.15 When it comes to amateurs, the mean number
of problems reported in this population can be considerably high,17
and may be related to the lack of orientation regarding vocal well-
being or lack of singing-specific vocal techniques.
It is also known that, usually, not even voice professionals,
who depend on specific vocal training18 oriented to their needs,
undergo vocal screening. Speech language may contribute to the
early identification of vocal problems, preventing phonotrauma
and ensuring good vocal function for a better professional
performance.19 They may present symptoms related to vocal
health,7such as throat clearing, secretion, hoarseness and dry
cough,20 or even neck pain or sore throat after long conversa-
tions, along with hoarseness or aphonia.21 On the other hand,
there are other aspects related to vocal behavior that can have
Accepted for publication March 2, 2016.
Presentations in Congress: The Voice Foundation’s 44th Annual Symposium: Care of
the Professional Voice, Philadelphia, Pennsylvania, United States, 2015; the 14th Foun-
dation Otorhinolaryngology Congress, São Paulo, Brazil, 2015; and the 23rd Brazilian Speech-
Language Pathology and Audiology Congress, Salvador, Bahia, Brazil, 2015.
From the Speech-Language Pathology and Audiology Department, Universidade Federal
de São Paulo—UNIFESP, São Paulo, Brazil.
Address correspondence and reprint requests to Milka Rosa, Rua 15 de Novembro 1356,
Jundiaí, SP, 13201-305, Brazil. E-mail: milkabrosa@gmail.com
Journal of Voice, Vol. ■■, No. ■■, pp. ■■-■■
0892-1997
© 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
http://dx.doi.org/10.1016/j.jvoice.2016.03.002
ARTICLE IN PRESS
an influence on vocal risk, such as technical difficulties, lack of
knowledge on voice production, wrong vocal classification, in-
correct use of voice, and lack of vocal training on warm-up and
cool-down techniques.22,23
The symptoms might lead to a handicap on their choir ac-
tivities, which are more easily observed in less experienced singers
than professional singers.12 In other words, the longer the sin-
ger’s experience, the lower is his or her vocal handicap.13 Modern
singers with vocal complaints present higher self-reported hand-
icap compared with individuals without vocal complaints and
with subjects who do not sing.24 Similarly, for church amateur
singers, the handicap is higher in individuals with voice altera-
tions, and similar between men and women, regardless of age,
voice type, and associated use of professional speaking voice.25
Other studies have reported that women present more voice dis-
orders than men, and that the most frequent complaints are related
to the lack of vocal technique.17 The vocal self-image or self-
assessment is also directly related to the vocal experience level,
being most commonly positive in experienced singers and neg-
ative in less experienced singers.26
The presence of three or more vocal symptoms27 should be
seen as indicative of a possible voice disorder, presenting a vocal
handicap in their choir activities, possibly evolving into dys-
phonia and affecting their quality of life.28 However, these
symptoms may be linked to emotional factors, such as mood dis-
orders associated with concerns and constant stress regarding
their vocal health29 and degree of trait anxiety.30
If, on one hand, choir singing has positive influences on cho-
risters’ emotional state, providing relaxation and well-being,31
on the other hand anxiety may hinder their performance.32 Some
factors tend to increase anxiety, such as difficulty with music,
physical health, and characteristics and behavior of the conduc-
tor, among others.32 Studies with amateur singers have shown
that anxiety is common among children and young choristers,
suggesting that anxiety could occasionally distract them from
or interfere with their performance.32 Researchers interested in
investigating anxiety in musicians have been usually studying
professional singers; relatively few studies have focused on the
experience of amateur choirs.
The following were the aims of this study:
(1) to investigate the existence of vocal risk in amateur
singers; and
(2) to map the vocal risk and analyze the contribution of
general voice signs and symptoms, specific singing hand-
icap, and generalized anxiety.
METHODS
A cross-sectional questionnaire study was carried out after ap-
proval was given by the Research Ethics Committee of the
Universidade Federal de São Paulo (CEP-UNIFESP n° 842.117).
The participants who were selected signed a free and informed
consent form. The invitation for participation in the study was
carried out through amateur choir conductors by phone or in person.
Initially, 38 amateur choirs from the city of São Paulo, Brazil,
were invited, which was equivalent to 926 choristers. The con-
ductors were provided with information about the purpose, design,
content, and length of the study. After this initial contact, the
researcher scheduled an appointment with each choir conduc-
tor on when to answer the questionnaires. Because of problems
in schedules, only 35 choirs were included in the study. The initial
data included 786 questionnaires filled in by choristers.
The data collection procedure included answering the per-
sonal identification and characterization form, the Voice Symptom
Scale (VoiSS),33 the Modern Singing Handicap Index (MSHI),24
and the Generalized Anxiety Disorder 7-item (GAD-7) scale.34
The choristers answered the questionnaires at their residences
or at the choir rehearsal site after the researcher provided a verbal
explanation about the aims of the study. The questionnaires were
then returned to the conductor, and then to the researcher. The
data were collected between September 2013 and January 2014.
Subjects were selected using the following criteria: older than
18 years, to be a member of the choir for over 6 months, and
to correctly fill in all of the questionnaires. These data were ob-
tained from each questionnaire. Subjects who were excluded were
those who presented with hearing impairments, as well as neu-
rologic, psychiatric, or psychological conditions, which could
prevent them from appropriately answering the questionnaires.
The data regarding the inclusion and exclusion criteria were ob-
tained from the answers of the participants.
After the inclusion and exclusion criteria were applied, the
final sample comprised 526 individuals from 35 choirs, 340
females and 186 males, with ages between 18 and 89 years (mean
age of 42.02 years). Figure 1 presents the flowchart of the cho-
risters included in the research.
The choirs selected for the study are maintained by univer-
sities, schools, churches, companies, hospitals, foundations,
institutions, or private funding. Their repertoire is eclectic, from
folkloric songs to sacred music, and playing a cappella or ac-
companied by a piano or other musical instruments.
Self-assessment questionnaires are convenient tools to screen
singers who might be at risk for vocal injury. The question-
naires are inexpensive and easy to administer. These protocols
are very subjective. They characterize the impact of a disease
or disorder on an individual’s quality of life.35 They have been
developed as a means of quantifying the impact of dysphonia.
In addition, they have been proven useful in helping conduc-
tors map the vocal risk of amateur choral singers for the purpose
of referral to otorhinolaryngologists and speech language pa-
thologists. Even in leisure activities, vocal care is necessary to
prevent vocal alterations.
The identification form was composed of closed and open ques-
tions on four aspects: identification data, chorister’s profile, general
health, and vocal self-assessment (Table 1).
On the term “profession,” participants were classified in seven
categories, according to the vocal demand and the style of voice
and speech expected for each profession. This classification was
based on the categorization adapted from Shewell.36 An extra
category (“others”) was developed by the authors to comprise
all the professions in the present study (Chart 1).
There are several self-assessment questionnaires translated into
and are validated for Brazilian Portuguese. In this study, par-
ticipants answered three questionnaires: the VoiSS,33,37 the MSHI,24
and the GAD-7 scale.34
ARTICLE IN PRESS
2Journal of Voice, Vol. ■■, No. ■■, 2016
The VoiSS38 self-assessment questionnaire is a vocal symp-
toms scale used to reflect physical, communicational, and
emotional symptoms implicit in an adult’s dysphonia.35 VoiSS
is considered a rigorous and psychometrically robust protocol
for vocal self-assessment,39,40 providing information about func-
tionality, emotional impact, and physical symptoms of voice
problems, including their consequences for all aspects of life.
This protocol has been validated for Brazilian Portuguese as
Escala de Sintomas Vocais (ESV).33 This version presents 30 in-
terrogative questions, each one scored from 0 to 4, according
to the frequency of occurrence: never, rarely, sometimes, almost
always, and always, respectively. From these questions, 15 regard
the limitation domain (functionality), 8 the emotional domain
(psychological effect), and 7 the physical domain (organic symp-
toms), which produce partial scores. Both the total score and the
scores for each domain are calculated by the simple sum of points.
The maximum score for the limitation domain is 60 points, for
the emotional domain 32 points, and for the physical domain
28 points, and the maximum total score is 120 points. The passing
score is 16 points,33 which means that the higher the scores in
this protocol, the higher the perception of the general level of
voice alteration regarding impairment, emotional reactions, and
physical symptoms reported. Scores lower than 16 indicate vocally
healthy individuals.
VoiSS undoubtedly provides significant results, although it is
not specifically designed for the singing voice. To meet the needs
of this public, Italian phoniatrist Franco Fussi41 developed the
MSHI and the Classical Singing Handicap Index, which are
adapted from the American protocol Voice Handicap Index.42
The MSHI protocol, which contains specific aspects of modern
singing styles, has a translated and culturally adapted version
for Brazilian Portuguese.24 It is composed of 30 items, divided
38 choirs contacted
926 choristers
Phone contact or
in person
35 choirs
786 choristers
Accepted to participate in
the study
3choirs
140 choristers
Could not participate in
the study due to schedule
problems
Distribution of the
questionnaires
721
questionnaires
returned
65
questionnaires
not returned
526
valid
questionnaires
195
questionnaires
excluded
89
choristers
Did not fill the
questionnaires entirely
33
choristers
Under 18 years
old
14
choristers
Diseases
- Older than 18 years
- In the choir for over 6
months
- Complete fulfillment of
the questionnaires
7
choristers
Hearing
impairments
59
choristers
In the choir for
under 6 months
4
choristers
Neurological
conditions
3
choristers
Psychiatric
conditions
FIGURE 1. Flowchart explaining questionnaire’s selection.
ARTICLE IN PRESS
Milka Rosa and Mara Behlau Mapping of Vocal Risk in Amateur Choir 3
into three subscales—disability, handicap, and impairment—
with functional, emotional, and organic domains, respectively.
The answers are marked with a 5-point scale, according to the
frequency of occurrence: 0 =never, 1 =almost never, 2 =some-
times, 3 =almost always, and 4 =always. The higher the score,
the greater the voice handicap observed by the individual singing.
The GAD-7 scale34 is a valid and reliable self-assessment
screening questionnaire43 for anxiety signs and symptoms. The
translation into Portuguese language was done by Pfizer (Copy-
right © 2005 Pfizer Inc., NewYork, NY), and there is evidence
of its validity in Brazil.44 It has been proven to be a valid screen-
ing tool to detect anxiety.45 The scale is composed of seven items,
and each question receives a score from 0 to 3 according to the
frequency of occurrence: not at all, several days, more than half
the days, and nearly every day. The scores are calculated by the
simple sum of points and vary from 0 to 21, evaluating the fre-
quency of anxiety signs and symptoms in the last 2 weeks. The
scores are classified as minimum risk (0–4 points), mild risk (5–9
points), moderate risk (10–14 points), or severe risk (15–21
points); thus, the higher the score obtained, the more anxious
the individual considers himself or herself. Scores of 10 points
or higher are considered positive indicator of anxiety signs and
symptoms. Statistical analysis adopted a significance level of 5%
(0.05).
The Tukey multiple comparison test was used to analyze the
means for the pass and fail groups and for all the VoiSS ques-
tions, as this test is used to test all the differences between the
two means.
The equality of two proportions test is a nonparametric test
that shows whether the proportion of answers of two deter-
mined variables or their levels is statistically significant. This
test was used to compare the pass and fail groups on the dis-
tribution of the variables profession and levels of anxiety, which
are qualitative, as well as to compare between genders regard-
ing the distribution of the variables pass and fail and levels of
anxiety.
Analysis of variance is a parametric test frequently used to
compare the means through variance. This test was used to analyze
the MSHI scores by comparing the means of the pass and fail
groups, as well as to compare the genders and the pass and fail
groups on their performances in all the questionnaires used in
this study.
The total sample was divided into pass and fail, according to
the results obtained from the VoiSS screening, which is consid-
ered an appropriate tool to classify the presence of voice
deviations.33
RESULTS
The mean total score on the VoiSS protocol for the sample was
17.57, which is almost two points higher than the passing score
of the instrument (16). The sample was divided into pass and
fail based on this score. The pass group included 255 subjects
(48.5% of the sample) with scores lower than 16 points, and the
fail group included 271 subjects (51.5%) with scores of 16 points
or higher (Table 2).
Pass and fail responses were analyzed according to the pro-
fession and the anxiety degree of the subjects (Table 3).
TABLE 1.
Sample Characterization (n = 526) According to Gender,
Singers’ Profile Data Regarding the Use of Singing Voice,
General Health Data, and Vocal Self-Assessment
Characterization n %
Gender
Female 340 64.63
Male 186 35.36
Profession
Artistic 35 6.65
Informants 62 11.78
Leaders and sellers 37 7.03
Did not answer 16 3.04
Others 320 60.83
Support 43 8.17
Transmitters 11 2.09
Voice of command 2 0.38
In how many choirs participates as singer?
1 choir 380 72.24
2 choirs 106 20.15
3 choirs 27 5.13
4 choirs or more 11 2.09
Did not answer 2 0.38
How many hours of practice per week?
Up to 2 hours 245 46.57
2–4 hours 177 33.65
4–6 hours 59 11.21
More than 6 hours 40 7.60
Did not answer 5 0.95
For how long have participated in the choir?
6 months to 1 year 98 18.63
1–3 years 141 26.80
More than 4 years 276 52.47
Did not answer 11 2.09
Use the voice in other activities?
Yes 169 32.12
No 342 65.01
Did not answer 15 2.85
Perform vocal warm up?
Yes 502 95.43
No 23 4.37
Did not answer 1 0.19
Perform vocal cool down?
Yes 64 12.16
No 425 80.79
Did not answer 37 7.03
Have had voice problems?
Yes 100 19.01
No 421 80.03
Did not answer 5 0.95
Have ever had voice treatment?
Yes 46 8.74
No 374 71.10
Did not answer 106 20.15
Have consulted an ENT specialist?
Yes 94 17.87
No 420 79.84
Did not answer 12 2.28
Have consulted a speech language pathologist?
Yes 52 9.88
No 463 88.02
Did not answer 11 2.09
Vocal self-assessment
Excellent 19 3.61
Very good 85 16.15
Good 312 59.31
Fair 102 19.39
Bad 6 1.14
Did not answer 2 0.38
ARTICLE IN PRESS
4Journal of Voice, Vol. ■■, No. ■■, 2016
The subjects who failed the screening were mostly from the
professional category “informants,” which includes teachers, lec-
turers, speech language pathologists, and advertising people34
(Chart 1).
Regarding anxiety, there were significant differences between
the pass and fail groups for subjects with minimal, mild, and
moderate anxiety degrees.
On the MSHI, statistically significant mean differences were
found between the groups in all subscales. The subjects who failed
the screening obtained the higher means on the subscales im-
pairment (10.53), disability (6.56), and handicap (3.87) (Table 4).
Categories
Vocal demand
Professionals
Support
Long periods using the voice with
frequent moments of silence; reduced
intensity, sometimes dealing with high
levels of stress.
Psychologists, architects,
administrators, analysts, engineers,
nurses, pharmacists, doctors, and
computer technicians.
Voice of command
Short periods using the voice with high
intensity and presence of background
noise. Weather or smoking may be
damaging factors.
Army sergeants, cops, players, barmen,
traders of the stock change,
auctioneers, pastors, postmen, and
outdoor workers.
Transmitters
Long periods using the voice with
microphone and earphone. High levels
of stress with possible aggressiveness
towards the listener, and little body
movement.
Receptionists and telemarketers.
Informants
Uninterrupted periods of speech,
varying the number of listeners and the
size of the space. High levels of
responsibility with the group of listeners,
using the voice to inform, persuade,
inspire, etc.
Speech-language pathologists,
lecturers, teachers, and people working
in advertising.
Leaders/Sellers
Usually short uninterrupted periods
speaking (less than the informants) at
high intensity, but with high relevance to
the use of voice in order to influence
people.
Attorneys, politicians, sellers,
managers, and business men and
women.
Artistic
Long periods of high vocal energy, high
level of ability to play a role and
emotionally convince. Body movement
variationisnecessary. Usuallyhas
vocal training.
Singers, actors, broadcasters, and
journalists.
Others
Short periods of voice use without great
vocal demand.
Retired men and women, students,
housewives, cooks.
CHART 1. Categorization of voice professionals according to the use of voice (adapted from Shewel, 2009).
TABLE 2.
Mean Total Score on the VoiSS Protocol, According to
the Passing Score (16)
Screening
VoiSS Protocol
n%
Mean
Total Score
Pass 255 48.5 8.27
Fail 271 51.5 26.34
Total 526 100 17.57
ARTICLE IN PRESS
Milka Rosa and Mara Behlau Mapping of Vocal Risk in Amateur Choir 5
When the genders were compared on the VoiSS screening,
it was observed that women failed more than men. They also
present higher anxiety levels (Table 5).
On the other hand, the performances were very similar between
men and women on the MSHI protocol, considering the VoiSS
screening results. There was a significant difference between
genders only in the disability subscale for the subjects who
passed the screening, and a tendency toward significance
in the impairment subscale for the ones who failed it
(Table 6).
TABLE 3.
Numeric and Percentage Distribution of the Choir Singers Regarding Their Profession and Anxiety Degree, According to
the Screening Results on the VoiSS Protocol
Profession and GAD-7
VoiSS Screening
Pvalue
Pass Fail
n%n%
Profession
Artistic 15 5.9 20 7.4 0.491
Informants 19 7.5 43 15.9 0.003*
Leaders and sellers 23 9.0 14 5.2 0.084†
Did not answer 8 3.1 8 3.0 0.902
Others 156 61.2 164 60.5 0.877
Support 25 9.8 18 6.6 0.186
Transmitters 8 3.1 3 1.1 0.104
Voice of command 1 0.4 1 0.4 0.966
Anxiety degree (GAD-7)
Minimal 161 63.1 87 32.1 <0.001*
Mild 86 33.7 139 51.3 <0.001*
Moderate 7 2.7 41 15.1 <0.001*
Intense 1 0.4 4 1.5 0.200
Note: Two-sample test for equality of proportions.
* Significant value (P≤0.05).
†Values tending toward significance.
Abbreviations: GAD-7, Generalized Anxiety Disorder 7; VoiSS, Voice Symptom Scale.
TABLE 4.
Distribution of Choir Singers According to the Results on the MSHI Subscales, Considering the Screening Results on the
VoiSS
MSHI and VoiSS
Screening n Mean Median Standard Deviation CV (%) Min Max CI Pvalue
Disability
VoiSS screening
Pass 255 1.85 1 2.87 155 0 20 0.35 <0.001*
Fail 271 6.56 5 5.78 88 0 31 0.69
Handicap
VoiSS screening
Pass 255 0.94 0 1.88 200 0 16 0.23 <0.001*
Fail 271 3.87 2 4.70 121 0 22 0.56
Impairment
VoiSS screening
Pass 255 3.33 2 3.98 120 0 24 0.49 <0.001*
Fail 271 10.53 10 7.18 68 0 34 0.86
Total
VoiSS screening
Pass 255 6.11 4 7.31 120 0 42 0.90 <0.001*
Fail 271 20.97 18 15.39 73 0 87 1.83
Note: Analysis of variance test.
* Significant values (P≤0.05).
Abbreviations: CI, confidence interval; CV, coefficient of variation; Max, maximum score; Min, minimum score; MSHI, Modern Singing Handicap Index; VoiSS,
Voice Symptom Scale.
ARTICLE IN PRESS
6Journal of Voice, Vol. ■■, No. ■■, 2016
All the questionnaires used in this study were
compared—VoiSS (screening), MSHI, and GAD-7—and sta-
tistically significant differences were found in all groups. The
highest total mean was obtained in the VoiSS screening (17.57),
for the subjects who failed (26.34). The lowest means were for
the subjects who passed the VoiSS screening (8.27) and the ones
who passed the MSHI (6.11). No traces of anxiety were found
among amateur choristers, as the total means, for both groups,
were below the passing score for the GAD-7 (10), as shown in
Table 7.
The mean values for each question of the VoiSS protocol were
compared according to the results on the screening (pass or fail).
The three higher means were for Q7—coughing or throat clear-
ing (1.33), Q16—difficulty speaking in noisy environments (1.21),
and Q1—difficulty being heard by others (1.17) (Table 8).
DISCUSSION
This study initially investigated the existence of vocal risk in
amateur choral singers using the VoiSS, which is a self-
assessment screening instrument that presents the perfect
classification.33 The results for the total sample showed the mean
value above the passing score (16), suggesting possible vocal
risk in the studied population (Table 2). Then, the participants
were grouped according to their screening results—pass (48.5%)
and fail (51.5%)—with the aim to further study the population
at risk for voice problems. Such classification was idealized to
facilitate the understanding of the relationship between voice
symptoms and vocal risk, and its overall impact on the quality
of life of choir singers.
Thus, using the equality of two proportions test in the statis-
tical analysis, it was observed that the screening results (pass
and fail) were related to the subjects’ professions and anxiety
levels (Table 3). The survey confirmed that subjects in the cat-
egory “informants,”36 which includes teachers, lecturers, and
others, revealed a significant prevalence of fail results (P=0.03).
Consequently, the impact of voice changes may interfere with
the amateur singer’s voice in other areas of life that are unre-
lated to musical activities10,46 (Table 3). This overlap of activities
increases their voice demand, which may increase the risk of
vocal alterations. A vocal alteration for a singer can be even
greater, as this might interfere with his or her professional life.47
Amateur singers present an intense vocal demand when the hours
of professional use and singing voice use are considered together.48
It is known that vocal care is recommended even when singing
is considered an amateur activity, as the amateurism in this mo-
dality, with no specific orientation, can lead to voice alterations.49
Vocal overload50 may increase the risk, and the sum of vocal
abuses may lead singers to a higher risk of presenting with vocal
symptoms.10
Anxiety and stress cause physiological changes in the body,
and consequently the structures that compose the vocal tract are
also affected, which results to modifications in vocal emission.51
In this study, the GAD scale34 was used to measure the state of
anxiety. In general, the anxiety levels were low, prevailing in
minimal and mild degrees, which indicates that amateur choir
singing does not contribute to increasing anxiety (Table 3). Many
professional singers mention mood disorders and stress related
to their vocal health, probably due to expectations regarding the
future of their careers. Hence, emotional factors are apparently
different for amateur singers, who do not suffer this pressure with
their singing.29 The choristers in the present study were from the
region of São Paulo, a city that, due to its complexity, may present
a higher probability for the individuals to develop psychologi-
cal problems and behavioral disorders.52 However, choir singing
is seen as a leisure activity, contributing to the reduction of stress
among participants. Our results confirm previous findings that
showed that amateur group singing produces positive emotions,
influencing the emotional state as well as the immunologic func-
tions in human beings. Thus, musical behavior possibly has a
positive influence on general well-being and health.31
The MSHI protocol is recommended to verify the impact of
a voice alteration in singers. The MSHI protocol and its subscales
were analyzed according to the VoiSS screening results, showing
significant differences between the pass and fail groups. The highest
mean was observed among the subjects who failed the screen-
ing in the impairment subscale, followed by the disability and
the handicap subscales (Table 4). Because the participants are
amateur singers and singing is not their primary source of income,
the results did not show great handicap, and the emotional subscale
presented the lowest mean in this protocol.17,53,54 Choristers are
aware when there is something wrong with their voice, and they
are able to indicate their limitation in the self-assessment.
The analysis of gender distribution on the VoiSS screening
(Table 5) showed that women presented greater potential for voice
problems, as 55% of them were classified as fail, whereas 45.2%
of the men composed this group. In previous studies, women
not only had a higher lifetime prevalence of voice disorders
(46.3% vs 36.9%), but also had a higher prevalence of chronic
TABLE 5.
Distribution of Choir Singers by Gender, According to the
Results on the VoiSS and GAD-7
VoiSS Screening
and GAD-7
Female Male
Pvaluen%n%
VoiSS screening
Pass 153 45.0 102 54.8 0.031*
Fail 187 55.0 84 45.2
VoiSS screening
and GAD-7
Pass
Minimal 88 57.5 73 71.6 0.023*
Mild 60 39.2 26 25.5 0.023*
Moderate 5 3.3 2 2.0 0.531
Intense 0 0.0 1 1.0 0.220
Fail
Minimal 54 28.9 33 39.3 0.090†
Mild 97 51.9 42 50.0 0.776
Moderate 33 17.6 8 9.5 0.084†
Intense 3 1.6 1 1.2 0.794
Note: Two-sample test for equality of proportions.
* Significant values (P≤0.05).
†Values tending toward significance.
Abbreviations: GAD-7, Generalized Anxiety Disorder 7; VoiSS, Voice
Symptom Scale.
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Milka Rosa and Mara Behlau Mapping of Vocal Risk in Amateur Choir 7
voice disorders than man.55 This may be due to the fact that there
are more women than men in professions who predispose them-
selves to present with voice complaints; these include professions
related to educational activities, as teachers have a higher rate
of self-reported voice disorders than those in other occupa-
tions. Furthermore, women not only reported higher rates of voice
disorders; in general, they also reported more chronic voice
disorders.55 It has been hypothesized that women are more vul-
nerable to voice disorders because of structural differences in
their laryngeal anatomy, as women have shorter vocal folds and
produce voice at a higher fundamental frequency.55 Previous
studies have identified differences between male and female teach-
ers in the report of voice problems. It has been shown that women
were significantly more likely to report voice problems associ-
ated with teaching.55,56 Hence, women are more likely to present
vocal disorders57,58 and, with minimal difference, women are more
anxious in the GAD-7 scale than men.17,58 Unlike professional
singers whose livelihood depends on vocal well-being,
amateur singers may not recognize the significance of a vocal
handicap.
The literature reveals that, in general, performing musicians
as a group are more anxious than nonmusicians. Female singers
have been shown as significantly more highly trait anxious than
the female non-singer population. However, it cannot be con-
cluded that female singers are more highly trait anxious than male
singers.59
In a previous study developed with music college singing stu-
dents, no difference was found between male and female subjects
regarding musical performance anxiety.59
On the other hand, men and women presented very similar
outcomes on the MSHI protocol when the VoiSS screening results
were considered (Table 6).
TABLE 6.
Distribution of Choir Singers by Gender, According to the MSHI Subscales, Considering the Screening Results on the
VoiSS
VoiSS Screening and MSHI n Mean Median Standard Deviation CV (%) Min Max CI Pvalue
Disability
VoiSS screening
Pass
Female 153 1.43 1.0 2.12 148 0 10 0.34 0.017*
Male 102 2.48 1.0 3.64 147 0 20 0.71
Fail
Female 187 6.66 6.0 5.96 90 0 31 0.85 0.693
Male 84 6.36 5.0 5.37 84 0 23 1.15
Handicap
VoiSS screening
Pass
Female 153 0.82 0.0 1.43 175 0 7 0.23 0.239
Male 102 1.12 0.0 2.39 214 0 16 0.46
Fail
Female 187 4.11 2.0 5.04 123 0 22 0.72 0.225
Male 84 3.36 2.0 3.84 114 0 17 0.82
Impairment
VoiSS screening
Pass
Female 153 3.14 2.0 3.39 108 0 17 0.54 0.690
Male 102 3.60 2.0 4.74 132 0 24 0.92
Fail
Female 187 11.04 10.0 7.52 68 0 34 1.08 0.078†
Male 84 9.38 8.0 6.26 67 0 26 1.34
Total
VoiSS screening
Pass
Female 153 5.39 4.0 5.70 106 0 31 0.90 0.154
Male 102 7.20 4.0 9.13 127 0 42 1.77
Fail
Female 187 21.81 18.0 16.32 75 0 87 2.34 0.180
Male 84 19.10 16.0 12.98 68 0 55 2.78
Note: Analysis of variance test.
* Significant values (P≤0.05).
†Values tending toward significance.
Abbreviations: CI, confidence interval; CV, coefficient of variation; Max, maximum score; Min, minimum score; MSHI, Modern Singing Handicap Index; VoiSS,
Voice Symptom Scale.
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8Journal of Voice, Vol. ■■, No. ■■, 2016
When all the protocols used in this study were compared
(VoiSS, MSHI, and GAD-7), as shown in Table 7, it was ob-
served that the VoiSS screening presented a total mean of four
points higher than the mean observed when the performance on
the MSHI protocol was selected. The results agree with the lit-
erature for the subjects who presented scores close to 20 on the
MSHI, as church amateur singers have presented a total mean
of 23 points on this instrument.25
Another study24 showed that amateur singers with com-
plaints presented 26.91 points and those with no complaints 16.91
points using the MSHI.24 In the GAD-7 scale, both groups were
below the passing score (≥10 points). This suggests an absence
of high anxiety traits in amateur choristers, although they live
in a stressful city. Because singing is a leisure activity, not a pro-
fessional one, the degrees of anxiety among this subject group
were minimal to mild.52 Thus, these protocols can assist speech
language pathologists and choir conductors in the selection
procedures.
The mean values for each question of the VoiSS protocol were
compared according to the results on the screening (pass or fail).
The higher means were found for the questions “Do you cough
or clear the throat?” (1.33), “Do you have difficulties speaking
in noisy environments?” (1.21), “Do you have problems calling
people’s attention?” (1.17), and “Do you have problems singing?”
(1.10). It was found that all the means presented values close
to one point, which corresponds to an answer between “rarely”
and “sometimes” (Table 8). Therefore, this score does not rep-
resent great vocal risk. Although this population sings as an
avocation, the impact of singing on the voice can have impli-
cations for its use in the workplace. Amateur choristers who
present with voice complaints or symptoms should seek assess-
ment from a medical professional. Greater understanding of
appropriate voice use could enhance the amateur’s choral singing
experiences. A qualified speech language pathologist could be
an invaluable asset to an amateur choral singing group by pro-
viding training in vocal hygiene and effective voice use.60
CONCLUSIONS
Even in a population that develops vocal activity for pleasure
or leisure, it is important to know the profile of the amateur cho-
risters in order to understand more broadly the risks and factors
that might diminish vocal health.
Based on the analyses performed in this study with amateur
singers, it may be concluded that there is vocal risk in this
population, higher for female singers and those with profes-
sions classified as “informants” (speech language pathologists,
lecturers, teachers, and people working in advertising). The anxiety
levels of the choristers were low, indicating that the activity is
not anxiogenic and may actually contribute to reducing stress
common to those who live in big cities.
There are vocal symptoms that place this population at po-
tential risk, and they are related to the higher handicap observed
in singing.
The combined use of two protocols identified a higher number
of choristers with potential problems than the use of these pro-
tocols separately.
Because amateur choristers appear to be at higher risk for voice
injury, an educational initiative on vocal health and well-being
seems warranted. The evaluation instruments used in this study
would appear to be of benefit for speech language pathologists
and choral conductors. The results of the screening process may
indicate the need for referral to a medical professional for further
assessment and training.
TABLE 7.
Distribution of Choir Singers According to the Results on the Instruments Used in the Study
Instrument n Mean Median Standard Deviation CV (%) Min Max CI Pvalue
VoiSS
VoiSS screening
Pass 255 8.27 9 4.26 52 0 15 0.52
Fail 271 26.34 24 9.27 35 16 68 1.10 <0.001*
Total 526 17.57 16 11.61 66 0 68 0.99
MSHI
VoiSS screening
Pass 255 6.11 4 7.31 120 0 42 0.90
Fail 271 20.97 18 15.39 73 0 87 1.83 <0.001*
Total 526 13.77 9 14.24 103 0 87 1.22
GAD-7
VoiSS screening
Pass 255 3.91 4 2.80 72 0 16 0.34
Fail 271 6.24 6 3.43 55 0 18 0.41 <0.001*
Total 526 5.11 5 3.34 65 0 18 0.29
Note: Analysis of variance test.
* Significant value (P≤0.05).
Abbreviations: CI, confidence interval; CV, coefficient of variation; GAD-7, Generalized Anxiety Disorder 7; Max, maximum score; Min, minimum score; MSHI,
Modern Singing Handicap Index; VoiSS, Voice Symptom Scale.
ARTICLE IN PRESS
Milka Rosa and Mara Behlau Mapping of Vocal Risk in Amateur Choir 9
Acknowledgment
The authors are indebted to Conselho Nacional de
Desenvolvimento Científico e Tecnológico—CNPq for funding
this research.
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6. Do you lose your voice? 0.27 0.97 0.63 <0.001*
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8. Is your voice weak/low? 0.37 1.30 0.85 <0.001*
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14. Do you get tired talking? 0.15 0.91 0.54 <0.001*
15. Does your voice problem make you stressed or nervous? 0.04 0.49 0.27 <0.001*
16. Do you have difficulties speaking in noisy environments? 0.64 1.75 1.20 0.714
17. Is it difficult to talk strong (high) or to yell? 0.39 1.38 0.89 <0.001*
18. Does your voice problem bother your family or friends? 0.03 0.31 0.17 <0.001*
19. Do you have a lot of secretion or phlegm in your throat? 0.49 1.37 0.94 <0.001*
20. Does the sound of your voice change during the day? 0.32 1.16 0.74 <0.001*
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23. Do people ask you what is wrong with your voice? 0.02 0.22 0.12 <0.001*
24. Does your voice seem hoarse and dry? 0.08 0.73 0.41 <0.001*
25. Do you have to make an effort to speak? 0.06 0.69 0.38 <0.001*
26. How often do you have throat infections? 0.66 1.22 0.94 <0.001*
27. Does your voice fail in the middle of a sentence? 0.16 0.83 0.50 <0.001*
28. Does your voice make you feel incompetent? 0.03 0.36 0.19 <0.001*
29. Are you ashamed of your voice problem? 0.01 0.23 0.12 <0.001*
30. Do you feel lonely because of your voice problem? 0.02 0.14 0.08 <0.001*
Total score 8.27 26.34 17.57
Note: Tukey test.
* Significant value (P≤0.05).
Abbreviation: VoiSS, Voice Symptoms Scale.
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10 Journal of Voice, Vol. ■■, No. ■■, 2016
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