ARTICLE IN PRESS Kuwaiti Teachers’ Perceptions of Voice Handicap *Sana A. Albustan, †Basem S. Marie, ‡Yaser S. Natour, and §Wesam B. Darawsheh, *Kuwait City, Kuwait, and †‡§Amman, Jordan
Summary: Objectives. The study aimed to investigate the effects of age, gender, level of education, experience, and class level taught on the perception of voice handicap by Kuwaiti teachers using the Arabic version of the Voice Handicap Index (VHI-Arab). The mean VHI scores of Kuwaiti teachers were compared with those of Jordanian and Emirati teachers. Methods. The study had a cross-sectional survey design. A total of 460 individuals (100 controls and 360 teachers) participated in this study and completed the paper copy of the VHI-Arab. We recruited 360 teachers, 180 males and 180 females (age range: 20–50 years), from 60 schools in 6 Kuwaiti districts. Teachers’ VHI scores were compared with 100 nonteaching voice users (50 males and 50 females, with an age range of 18–42 years). Results. Female teachers scored significantly higher than male teachers in all subscales (ie, physical: P = 0.02; emotional: P = 0.007; total: P = 0.017), except for the functional subscale (P = 0.147). Elementary school teachers scored significantly higher than teachers of other levels (middle and high school) in all VHI subscales (physical: P = 0.047; emotional: P = 0.01; total: P = 0.039), except for the functional subscale (P = 0.47). The mean score of Jordanian teachers was higher than that of Kuwaiti and Emirati teachers in all VHI subscales. Conclusions. Teachers with a more favorable teaching environment scored better on the VHI. Gender differences were found in all the Arabic nationalities studied. Female teachers of the elementary level, in particular, should be the focus of attention of efforts to prevent voice damage. Key Words: Occupational voice users–Occupational health–Perception of handicap–Teachers–Voice Handicap Index (VHI-Arab).
INTRODUCTION Teachers as occupational voice users Teachers are considered to be occupational voice users. As they use their voices continuously over extended periods of time, they have to speak loudly, project their voices, and manipulate their voice tone.1–5 Because of their excessive use of voice and the demands of their profession, teachers often abuse their voice, and thus they have a strained, tired, or hoarse voice.1–9 Therefore, teachers may be at risk for developing voice disorders.10,11 The literature showed that research has been focused on comparing the representation of voice disorders between teachers, as occupational voice disorders, and nonteachers. For example, Roy et al6 found that teachers had a higher prevalence of voice disorders than nonteachers. Teachers also had a higher prevalence of dysphonia and abnormal acoustic features than nonteachers.12 Further, the acoustic and perturbation measures of teachers changed (higher fundamental frequency [F0], sound pressure level, and lower jitter and shimmer) during the working day.13 Gender and voice disorders Gender was one major differentiating factor within the group of teachers. Russell et al14 found that female teachers were more Accepted for publication May 3, 2017. From the *Department of Communication Disorders sciences, Kuwait University, Kuwait City, Kuwait; †Audiology and Speech-Language Department, Al-Ahliyya Amman University, Amman, Jordan; ‡Department of Hearing and Speech Sciences, Faculty of Rehabilitation Sciences, The University of Jordan, Amman, Jordan; and the §Department of Occupational Therapy, Faculty of Rehabilitation Sciences, The University of Jordan, Amman, Jordan. Address correspondence and reprint requests to Basem S. Marie, Audiology and Speech-Language Department, Al-Ahliyya Amman University, Amman, Jordan. E-mail:
[email protected] Journal of Voice, Vol. ■■, No. ■■, pp. ■■-■■ 0892-1997 © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jvoice.2017.05.003
prone to be affected by voice disorders than male teachers. Similarly, Laukkanen et al13 found that female teachers experienced more throat fatigue than male teachers after the working day. Differences between males and females are most probably due to anatomic and physiological differences.6,14 For example, a shorter, smaller cross-sectional mass and a higher tension of the female vocal folds produce higher F0s, which renders female voice users more prone to voice disorders.15 Voice Handicap Index (VHI) as a method of self-assessment of voice handicap In addition to the classical assessment methods using acoustic and aerodynamic measures, other methods of assessment of voice handicap have evolved, such as the VHI, established by Jacobson et al.16 The World Health Organization’s International Classification of Functioning, Disability, and Health17 states that a handicap is a limitation in an individual’s activities arising from a disorder and the personal, social, and environmental factors that may change the individual’s perception of this disorder.17,18 The VHI has been introduced as a tool to assess peoples’ perception of their voice handicap. It is a self-assessed questionnaire that consists of 30 questions clustered under three subscales, that is, physical, functional, and emotional.16 Using the VHI allows individuals to assess the perception of their voices by how voices affect their lives.16 The VHI gives a valid and reliable indication of the clients’ perception of their voice disability and can be used as a measure of a clients’ quality of life resulting from the disability.19 The VHI is also used to compare perceptions of voice pretreatment and posttreatment20–25 and to compare voice characteristics before and after phonosurgeries.26–28 The VHI has been widely used to determine whether professional voice users (teachers in particular) perceive their voice as handicapped.16,29,30
ARTICLE IN PRESS 2 VHI has been translated into multiple languages. Some of these VHI translations are available in different languages, such as German,31 Portuguese,32 Polish,33 Swedish,34 and Arabic.30 The Arabic version of the VHI (VHI-Arab) has been used as a tool to examine Jordanian29 and Emirati teachers’ perception of their voices.35 The latter studies suggested that exceeding a cutoff score in VHI-Arab is an indicator of a perception of voice handicap. Thus, this tool could be used in clinical settings with traditional acoustic and aerodynamic measures to formulate more reliable clinical decisions. The aim of the study Because Kuwait is considered a separate demographic and geographic area, studying Kuwaiti teachers’ perception of voice handicap is an important step toward reaching a comprehensive paradigm concerning the perception of voice handicap in the Arab region. Kuwaiti teachers have never undergone such an investigation before. This may pave the way toward identifying factors that may increase the perception of voice handicap and the ways to counteract them. The investigation could also assist in identifying the level of awareness and knowledge of Arab teachers (across different Arab countries) of factors related to preserving vocal health and avoidance of other factors that can be deleterious. The level of involvement of speech pathologists can also be identified, and the level of care provided by schools to teachers can be explored. In addition, the current study may shed light on the teaching circumstances and measures taken by the educational systems to promote a sense of satisfaction among teachers. Thus strategies to increase and promote awareness and knowledge about occupational voice health can be identified, and other strategies that can decrease the level of perception of voice handicap among teachers can be delineated. The current study aimed to compare responses using the VHIArab between elementary, middle school, and high school teachers and a control group. Teachers’ age, gender, level of education, experience, and student level taught were used as covariates to be tested. In addition, this study aimed to compare mean scores on functional, physical, emotional, and total scores of the VHIArab among Kuwaiti, Emirati, and Jordanian teachers. The hypothesis was that there is a difference between the VHI scores between the Kuwaiti teachers and the control group and that gender has a significant effect on VHI scores. METHODOLOGY Participants and procedure A cross-sectional survey design was employed in this study, and the method of sampling was convenience sampling. Concerning the case group, six schools from each of the following Kuwaiti districts were chosen at random (Ahmadi, Capital, Hawalli, Jahra, Mubarak Al-Kabeer, and Farwaniya). The teacher:student ratio varied from school to school, ranging from 1:19 to 1:35. Teachers who participated in this survey had different teaching loads, ranging from teaching 6 to 20 hours per week depending on the teaching disciplines. Teachers from various age levels, education levels, years of teaching experience, and student levels taught were invited to participate in the study. The study was conducted
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in the middle of the first semester to nullify the effect of fatigue occurring at the end of the semester versus the effect of vocal rest at the beginning of the semester. A convenience sample was used as a control group. Subjects in the control group were not occupational voice users. They self-reported that they did not suffer any medical problem that may affect their voice production at the time of data collection. The translated and validated paper version of the VHI-Arab by Saleem and Natour30 was used in this study. Written formal consent before participation was required, and participants were informed that they had the right to withdraw from participation at any point without any consequences. A convenience sample of 10 teachers from each school was selected to participate in the study. They were approached through the principals of the schools after we had explained the aims of the study and presented them with the Ministry of Education formal ethical approval to conduct the study. The teachers were then approached at their free time (break time or free classes) and asked to provide their formal written consent to participate in the study after the aims and rationale had been explained to them. They were then handed the paper copy of the VHIArab and were asked to complete it and then return it. Inclusion and exclusion criteria Only participants who gave their informed consent voluntarily to participate were included in this study. Both the experimental and the control groups were required to be free of vocal or respiratory complaints. This was determined by the method of self-report where participants were asked whether they had laryngeal or respiratory infections or whether they had been hospitalized for such reasons. Statistical analysis Data were analyzed using SPSS Version 22.0 (2016, IBM Corporation, Armonk, NY). For the statistical analyses conducted in the study, an alpha value of 0.05 was predetermined as the level for significance. A test of analysis of variance was conducted to compare the control group scores with the teachers’ scores on the three subscales of VHI-Arab (physical, functional, and emotional) and in the total score of the test to determine whether there were significant differences between the two groups. A multivariate analysis of variance was conducted to determine whether there were significant differences in teachers’ scores on the three subscales of VHI-Arab (physical, functional, and emotional) and in the total score of the test across gender, age, level of education, years of experience, and level of students taught. For comparison purposes, the cutoff scores for VHI-Arab subscales and total score were adopted from the study conducted by Marie et al29 as follows: physical = 7.34, functional = 7.6, emotional = 3.71, and total score = 16.55. RESULTS The following subsections present the demographic data of participants and the results of the statistical analysis of the effect of factors (ie, group [case-control], gender, level of students taught, educational level, age, and level of experience) on VHI scores.
ARTICLE IN PRESS Sana A. Albustan, et al
of age was 30–40 years (n = 161, 45%). The education level of teachers ranged from bachelor’s degree to postgraduate level, with the most frequently observed category of diploma (n = 180, 50%). Years of experience ranged between 0 and 15 years, and the most frequently observed category was 0–5 years (n = 118, 33%). Table 1 summarizes the demographic data of teachers.
TABLE 1. Demographics of Case Group (Teachers’ Group) Variable Age 20–30 30–40 40–50 50+ Missing Educational level Bachelor’s Diploma Medical Other Postgraduate Missing Years of Experience 0–5 10–15 5–10 15+ Missing Gender F M Missing Location Ahmadi Capital Farwaniya Hawalli Jahra Mubarak Al-Kabeer Missing
3
Kuwaiti Teachers’ Perceptions of Voice Handicap
n
%
117 161 62 20 0
32 45 17 6 0
132 180 1 33 14 0
37 50 0 9 4 0
118 83 95 64 0
33 23 26 18 0
180 180 0
50 50 0
60 60 60 60 60 60 0
17 17 17 17 17 17 0
Case-control group comparison Table 2 demonstrates the VHI scores (in all subscales and total score) according to group, gender, and level of students taught. There were significant differences between teachers and controls in the scores of functional (F = 17.81, P = 0.000), physical (F = 17.60, P = 0.000), emotional (F = 18.59, P = 0.000), and total score (F = 22.98, P = 0.000) of the VHI-Arab. Effect of gender on VHI scores Females scored higher than males in all subscales in addition to total VHI, as shown in Table 2. Female teachers differed significantly in comparison with male teachers in the scores of the physical subscale (F = 5.38, P = 0.02), the emotional subscale (F = 7.38, P = 0.007), and the total score of the VHI-Arab (F = 5. 78, P = 0.017). However, there were no significant differences in the scores of the functional subscale (F = 2.18, P = 0.147). We noted that female teachers exceeded the cutoff scores as established by Marie et al29 on the emotional subscale and the total score. However, they did not exceed the cutoff scores on both the physical and functional subscales. Male teachers, on the other hand, did not exceed the cutoff of any of the subscales nor the total VHI score. A VHI score (on any of the VHI subscales or total score) exceeding the established cutoff scores does not conclusively indicate the presence of a voice disorder, rather this indicates a condition that warrants further evaluation using other assessment tools for the purpose of verification of the presence of a voice disorder.
Notes: Due to rounding errors, percentages may not equal 100%.
Demographics of participants Responses from 100 controls (50 males and 50 females) were used for comparison. In the teachers’ group, there were 360 Kuwaiti school teachers (180 males and 180 females). The age range was 20–50 years, and the most frequently observed category
Effect of age, level of experience, educational level, and level of students taught on VHI scores There was no significant difference between different age groups in any of the scores of the VHI subscales (functional: F = .4,
TABLE 2. VHI-Arab Scores as Arranged by (Group, Gender, and Level of Class Taught)
Group Teachers Controls Gender Male Female Level of class taught Elementary schools Mid schools High schools
VHI Functional (µ ± SD)
VHI Physical (µ ± SD)
VHI Emotional (µ ± SD)
VHI Total (µ ± SD)
6.38 ± 4.3 4.3 ± 3.04
6.76 ± 5.59 4.32 ± 3.27
3.73 ± 4.79 1.57 ± 2.12
16.83 ± 13.11 10.3 ± 6.26
6.05 ± 3.93 6.7 ± 4.63
6.07 ± 4.88 7.43 ± 6.19
3.05 ± 4.2 4.41 ± 5.27
15.18 ± 11.45 18.48 ± 14.46
6.68 ± 4.43 6 ± 4.23 6.47 ± 4.15
7.78 ± 6.54 6.16 ± 5.31 6.33 ± 5.31
4.64 ± 5.15 2.79 ± 4.73 3.78 ± 4.73
19.1 ± 14.54 14.83 ± 12.71 16.58 ± 12.71
Abbreviations: µ, mean; SD, standard deviation; VHI, Voice Handicap Index.
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TABLE 3. Mean scores Comparisons of the VHI-Arab Scores of the Jordanian, Emirati, and Kuwaiti Teachers
Kuwait Emirati Jordanians
VHI Functional (µ ± SD)
VHI Physical (µ ± SD)
VHI Emotional (µ ± SD)
VHI Total (µ ± SD)
6.38 ± 4.3 4.94 ± 4.24 7.17 ± 4.90
6.76 ± 5.59 6.24 ± 5.61 8.25 ± 6.11
3.73 ± 4.79 3.15 ± 4.70 4.99 ± 6.03
16.83 ± 13.11 14.38 ± 12.65 20.37 ± 15.24
Abbreviations: µ, mean; SD, standard deviation; VHI, Voice Handicap Index.
P = 0.75; physical: F = .10, P = 0.96; and emotional: F = .13, P = 0.94), nor in the total VHI-Arab score (F = .17, P = 0.92). Similarly, there was no significant difference among groups of levels of experience in any of the scores of the VHI subscales (functional: F = .70, P = 0.55; physical: F = .66, P = 0.58; and emotional: F = .50, P = 0.68), nor in the VHI-Arab total score (F = .66, P = 0.58). Participants’ educational level showed no significant differences in all the VHI subscales (functional: F = .23, P = 0.80; physical: F = .16, P = 0.85; and emotional: F = .30, P = 0.74) and even in the VHI-Arab total score (F = .08, P = 0.92). Further, the level of class taught as a variable revealed a significant difference in the physical subscale (F = 3.08, P = 0.047), the emotional subscale (F = 4.56, P = 0.01), and the total VHIArab score (F = 3.265, P = 0.039) but not in the functional subscale (F = .768, P = 0.47). The Tukey post hoc test revealed that elementary school teachers had significantly more perception of voice handicap than middle and high school teachers. VHI scores comparison across Arab nationalities We compared the mean values of raw scores of Kuwaiti teachers obtained in this study and those obtained for the Jordanian and Emirati teachers from Marie et al29 and Natour et al,35 respectively. Teachers’ mean subscales and total scores revealed that Jordanian teachers had the highest mean scores across the board in all the VHI subscales and total score, followed by the Kuwaiti teachers and then the Emirati teachers. Table 3 illustrates these comparisons of mean scores. DISCUSSION The purpose of this study was to investigate Kuwaiti teachers’ perception of voice handicap and to compare it with that of nonoccupational voice users. Another aim was to compare the perception of handicap among three Arab nationalities (Jordanian, Kuwaiti, and Emirati) by reporting raw scores. The effects of factors such as gender, age, level of experience, level of education and level of students taught on the perception of voice handicap were also explored. There were significant differences between the VHI scores of Kuwaiti teachers and controls; in addition, there were significant effects of factors such as gender and level of students taught on VHI scores. The following sections are aimed at discussing these results in light of the literature review.
The VHI: a toolbox component for the evaluation of voice disorders The presence of significant differences between teachers and control volunteers in their scores on functional, physical, emotional subscales, and the total score of the VHI-Arab was expected. Although the VHI is about the perception of vocal handicap regardless of the physical condition of the larynx, it can be used alongside other assessment tools for the identification and evaluation of voice disorders and treatments used. Additionally, the findings within each VHI subscale could be explored further to investigate risk factors for voice impairment. An example would be the physical subscale, where stronger teacher perception of physical discomfort from their voice characteristics may comprise the basis for more formal forms of evaluation (eg, acoustic, aerodynamic, or stroboscopic evaluation). In fact, sometimes teachers may focus more on relating their message to their students and overlook some important vocal hygiene and healthy voice use rules.35 The results from Roy et al6 found that the prevalence of voice disorders is higher in teachers than in nonteachers. This also agrees with the results of the study conducted by De Medeiros et al,12 who found that the prevalence of dysphonia was higher in teachers than in nonoccupational voice users. Teachers are considered occupational voice users, and therefore have the expected result of a heightened perception of handicap due to their voice use, which may make them more susceptible to voice disorders. Thus, the VHI can be used in combination with other objective methods of assessment for conducting a reliable assessment of voice disorders. Gender and the perception of voice handicap Female Kuwaiti teachers exceeded the cutoff scores in the emotional and total scales, while the corresponding male teachers did not exceed any of the cutoff scores as established by Marie et al.29 This meant that the perception of voice handicap of male Kuwaiti teachers was within the normal accepted range. However, the female Kuwaiti teachers exceeded the normal range of perception of handicap in the emotional VHI subscale, and this affected the VHI total score, causing it to be beyond the expected normal level as well. Female teachers scored higher than males in all subscales, in addition to total VHI. In addition, female teachers differed significantly in comparison with male teachers in the total score of the VHI-Arab physical and emotional subscales. Further, there was no significant difference in the functional subscale. These results agree with Russell et al,14 who found that female teachers
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Kuwaiti Teachers’ Perceptions of Voice Handicap
were more affected by voice disorders than male teachers, and Laukkanen et al,13 who stated that female teachers feel more throat fatigue than male teachers at the end of a working day. As such, it is expected that they would have a higher perception of vocal handicap. This could be due to voice habits, cultural issues (teaching being a female-dominated career in the Arab world), in addition to a possible physiological contribution such as the higher F0 in females. The significant difference in the physical, emotional, and total scores between male and female teachers might be related to the higher perception in females in terms of emotional response toward their vocal output. Additionally, it seemed that female teachers had a stronger perception of physical discomfort toward their voice characteristics. Overall, these collective differences are mainly related to anatomic and physiological laryngeal differences between males and females, as Roy et al6 and Russell et al14 have stated. The functional subscale mainly reflects the impact of the perception of voice handicap on daily life activities.29 As such, it seemed that Kuwaiti male and female teachers were active in terms of voice use in daily life activities. However, the data showed a trend that females had a higher, although not significantly higher, perception of voice handicap on the daily life activities. This may be because of more feminine activities in the social context of Kuwait. It has been observed that Kuwaiti women are active participants in social, artistic, and financial matters, which may have added to vocal handicap perception in Kuwaiti female teachers. Other factors that affect the perception of voice handicap Two results were of particular interest: one was that the level of students taught by teachers showed significant differences in the physical and emotional subscales and the total VHI-Arab scores. The second was that elementary school teachers had significantly more perception of voice handicap than teachers of middle and high school. This meant that the elementary school teachers had more perception of laryngeal discomfort and more perception of emotional stress. This may be understandable because the elementary age group is known to demand high levels of classroom control and the repeated use of the voice. These scores indicated more vocal stress, with several repetitions of presented ideas. There was no significant difference in the functional subscale associated with the level of students taught, because this subscale is related to daily life activities, which could be considered as daily routine classroom activities reflected at all student levels. VHI scores comparison across Arab nationalities A comparison among Jordanian, Emirati, and Kuwaiti teachers’ mean raw scores of subscales and total scores (Table 3) reveals that Jordanian teachers had the highest mean scores across the board in all the VHI subscales and the VHI-total score, followed by the Kuwaiti teachers and then the Emirati teachers. This might be due to the larger number of students per classroom in Jordan, especially with waves of newly enrolled students who were the result of recent unrest in the region. Room acoustics
5
may be another contributing factor. School buildings are usually rental buildings that may not always comply with good room acoustics. Further, most classrooms in Jordan, for example, may not have proper amplification systems. Another reason could be that the teachers in UAE and Kuwait receive more advice on vocal matters and treatment by speech pathologists through the teaching system. An additional stress factor might be the lower wage rates for Jordanian teachers than for Kuwaiti or Emirati teachers, and several Jordanian teachers commented on that fact. Lower wages lead to general unrest and a lower quality of life. Limitations of the study and future research The current study did not verify the vocal health status of the participants through formal assessment techniques (such as videostroboscopy) and relied on their self-report of not having a voice disorder. Future studies will include a formal evaluation as part of the procedures. Future studies should also target other Arab nationalities and should compare their scores through inferential statistics. CONCLUSION Kuwaiti teachers had a higher perception of voice handicap than the control group of nonoccupational voice users. These results reflected possible behaviors by teachers that are damaging to the voice while instructing their students. Further, gender of teachers and level of students taught contributed to the perception of voice handicap. Female Kuwaiti teachers had significantly higher VHI scores (except for the functional scale) than male Kuwaiti teachers. This may relate to the tendency of female teachers to use their voice more often while teaching. This may also be exacerbated by the additional load exerted on the voice while participating in numerous social activities and gatherings, which are known to be part of the female social synthesis of the Kuwaiti culture. In addition, female teachers may tend to be more emotionally sensitive in monitoring their voices, which results in a higher emotional VHI scores than males. However, functionally the perception of handicap for both genders was the same due to the overt and tangible effect of the use of voice while teaching. This could also be due to voice habits, cultural issues (teaching being a female-dominated career in the Arab world), in addition to a possible physiological contribution such as the higher F0 in females. The conditions of teaching, such as number of students in a class, may induce behaviors that damage the voice, which may affect the perception of voice handicap among teachers. The level of voice care and monitoring provided in schools for teachers also may affect the perception of handicap. The level of involvement of speech pathologists in schools can also affect the level of care provided for teachers and their perception of voice satisfaction or handicap. These conclusions were reflected by the difference in the results between the VHI scores of the Jordanian teachers versus the Emirati and the Kuwaiti teachers. Probably the Jordanian teaching environments exert more pressure on voice abuse, and thus elicit traumatic voice behaviors, which may have led to a high perception of handicap among Jordanian teachers.
ARTICLE IN PRESS 6 This study showed that the conditions of teaching in different Arab countries need to be considered to guarantee a higher level of satisfaction and a lower perception of voice handicap among teachers. In addition, this study identified the categories of teachers that should be a priority for efforts directed at preventing voice disorders and reducing the perception of handicap. These categories are teachers at the elementary level of teaching and those who are females in particular. Further research studies need to be directed at investigating the optimal teaching environment to guarantee the highest level of teaching satisfaction and the lowest level of voice handicap among teachers as occupational voice users.
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