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Table of Contents
ORIGINAL ARTICLE
Year : 2010  |  Volume : 12  |  Issue : 2  |  Page : 31-40

Voice disorders among Saudi teachers in Riyadh City


Consultant, Assistant Professor of Phoniatrics Communication and Swallowing Disorders Unit (CSDU) ,ORL Department, King Abdulaziz University Hospital, Riyadh, Saudi Arabia

Date of Web Publication2-Jan-2020

Correspondence Address:
MD, PhD Khalid H Malki
P.O Box 245 - Riyadh, 11411 ORL Department, Communication and Swallowing Disorders Unit (CSDU) King Abdulaziz University Hospital Riyadh
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1319-8491.274630

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  Abstract 


Background and Objectives: The teaching voice and its impact on the teaching profession have gained a special interest in several studies concerned with occupational voice disorders. To the best of our knowledge, no study had investigated this problem among Saudi teachers. This study aimed at investigating the prevalence of voice disorders among Saudi teachers in Riyadh city in addition to the possible risk factors to these disorders.
Subjects and Methods: A voice questionnaire was distributed to a random sample of Saudi teachers in Riyadh city. The study included 416 teachers with a mean age of 34.3±5.2 years. Based on the results of the self-administered questionnaires, teachers with voice complaints (TVC) were identified. Significant differences between teachers regarding possible risk factors were investigated.
Results: Thirty three percent of Saudi teachers in Riyadh city reported to have voice problems. Females were significantly more prone to develop voice problems than males. Teachers who reported the presence of some living habits, teaching characteristics, and health conditions were significantly at higher risk of developing voice disorders.
Conclusion: Voice problems seem to be a prevalent problem among Saudi teachers in Riyadh city. Such condition could have negative impacts on the teaching profession. There appears to be many risk factors that can significantly affect the voice quality of teachers.

Keywords: Voice disorders – Teachers – Occupational – Prevalence.


How to cite this article:
Malki KH. Voice disorders among Saudi teachers in Riyadh City. Saudi J Otorhinolaryngol Head Neck Surg 2010;12:31-40

How to cite this URL:
Malki KH. Voice disorders among Saudi teachers in Riyadh City. Saudi J Otorhinolaryngol Head Neck Surg [serial online] 2010 [cited 2022 Nov 30];12:31-40. Available from: https://www.sjohns.org/text.asp?2010/12/2/31/274630


  Introduction Top


Several studies have shown the high prevalence of voice disorders among teachers, and that teachers reported frequently-occurring vocal symptoms. In most of these studies, data have been collected through questionnaires and the prevalence of symptoms varies from 12% to 26% depending on the population and the method used[1],[2].

Teachers constitute a significant proportion of patients seeking medical help for voice problems. They are at risk for vocal disorders because they have to speak over high background noise levels, they naturally increase their vocal loudness, which causes an increase in the mean fundamental frequency (Fo), and they show a strained or hyperfunctional vocal behavior, mostly in untrained speakers [5].

Roy et al [6] reported that teachers have significantly more voice complaints than the general population. Such complaints include vocal fatigue, change in voice, increased phonation effort, dry throat, throat tightness, sore throat, etc.[7].

In the teaching profession, the need for voice perfor-mance and endurance is exceedingly high. These findings brought about the need to study the prevalence and epidemiological aspects of voice problems in teachers. Moreover, it has been suggested that voice disorders should be diagnosed and treated early, preferably before or during training for this profession [8]. It has been recommended that routine screening of prospective teachers for susceptibility to voice disorders could prevent vocal dysfunction [9]. Many researchers have been trying to develop prevention programs for teachers with risk factors and those who already experienced voice difficulties. However, these research findings were mostly based on comparisons between teachers and non-teachers [4],[6],[10],[11]. Only a few of them were from within teachers’ groups [3],[12],[13] and even fewer had included male teachers. The inherently different vocal loading between teaching and non-teaching groups makes their respective voice-related problems fundamentally different. Evaluating within teachers’ groups allows analyzing the influence of different teaching characteristics, such as years in occupation, subjects taught, vocal loudness in the classroom, etc on voice problems for teachers [7]. Currently, there are no published studies about voice problems in Saudi teachers. The aim of this study was to analyze the prevalence of voice problems among Saudi teachers in Riyadh, the capital city of Saudi Arabia, to investigate the factors that could influence this problem, and to compare the prevalence of voice disorders between male and female Saudi teachers.


  Materials and Methods Top


Questionnaire

The questionnaire of this study was developed based on the clinical experience of the author and on other similar reports used in many studies investigating professional voice disorders [4],[6],[14],[15],[16],[17],[18]. The items explored in the questionnaire included a variety of parameters that might have an influence on the vocal performance of a teacher. The information in the administered questionnaire included: [1] demographic data, [2] teaching information such as the teaching grade, courses taught, number of students in the class, number of teaching sessions per week, years of experience in the field of teaching, etc, [3] presence of vocal symptoms related to teaching such as change of voice, voice fatigue, throat dryness, sore throat, frequent throat clearing, globus throat sensation, etc, [4] living habits such as smoking, loud speaking voice during regular conversations, and family history of voice problems, etc, [5] other health problems that cloud have an influence on voice, such as repeated upper respiratory tract infections, allergies, chronic cough, laryngo-pharyngeal reflux, etc, and [6] functional impact of voice problem on the teaching career such as absenteeism from work. This study was approved by the Research Center of College of Medicine, King Saud University, and its Ethics Committee. In this cross-sectional study, the above described questionnaire was self-administered by the participants themselves. The selection of the sample was done using stratified random sampling method. The voice questionnaire was distributed to a random sample of 270 Saudi male and 270 Saudi female teachers in the nine sectors of Riyadh city. Three elementary, three intermediate, and three secondary schools were selected randomly in each Riyadh region. Ten teachers were selected also randomly in each school. Saudi teachers who were actively participating in teaching elementary, intermediate or secondary schools were included in the study.

Statistical analysis

Chi-square test was used as the test of comparison and/or association between the study variables. Odds ratios (OR) and 95% confidence intervals (95%CI) were calculated to measure the magnitude of risk. All calculations were conducted using the SPSS 11.0 (SPSS Inc., Chicago, IL). The level of significance was set at p ≤ 0.05.


  Results Top


Out of the 540 questionnaires distributed, 428 were collected. Twelve questionnaires were excluded because of incomplete data. There fore, 416 questionnaires were included in the study, and response rate, accordingly. The study sample was composed of 222 female (53.4 %) and 194 male (46.6 %) teachers, with a mean age of 34.9 years (SD 6.5) for males, and 33.7 years (SD 3.6) for females. Thirty three percent of participants (140 teachers) showed at least one voice complaint at the time of investigation. Therefore, 140 participants were considered as teachers with voice complaints (TVC). In this group, 45 teachers were males (32.1 %) and 95 teachers were females (67.9 %).

Demographic characteristics and some living habits

[Table 1] shows the distribution of the demographic data, some living habits, and family history of voice disorders among TVC. There was a highly significant statistical difference between the percentage of female participants having voice complaints and male teachers with voice problems. More female teachers had reported having voice problems than male teachers. Regarding the living habits, only 26% of teachers who participated in this study reported themselves as smokers. However, there was no significant statistical difference between teachers who smoke and those who do not. Comparison between the teachers who had the habit of loud voicing and those who did not, showed that the teaches who had the habit of loud voicing showed significantly more voice complaints than the teachers who denied this habit. The statistical difference was highly significant. Positive family history was another factor that showed highly significant statistical difference. Teachers with positive family history of voice problems had more vocal complaints than teachers with negative family history. On the other hand, there was no significant statistical difference demonstrated within TVC regarding the age group, marital status, or the number of the household offspring.
Table 1: Distribution of demographic characteristics, some personal habits, and family history of voice disorders among teachers with voice complaints (TVC).

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Teaching characteristics

The teaching characteristics data for TVC are reported in [Table 2]. On comparing teachers in this group regarding the grade taught, significantly less teachers in the primary schools reported having voice complaints than those in the secondary and intermediate schools. Regarding the course taught, only science teachers reported significantly higher proportions of voice problems than other courses. Also, a significant difference has been demonstrated within TVC regarding the number of students in the class. Significantly higher rates of voice problems were reported in those teachers who used to teach more than 30 students/class. No statistical significant differences were reported among TVC neither regarding the years of teaching experience nor the number of sessions given per week.
Table 2: Distribution of teaching caracteristie variables among teachers with voice complaints (TVC).

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Voice-related symptoms

The distribution of voice-related symptoms among TVC is shown in [Table 3]. TVC demonstrated statistically significant higher proportion rates of vocal symptoms than those who did not report the presence of such symptoms.
Table 3: Distribution of voice related symptoms among teachers with voice complaints (TVC).

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Health conditions that could have an influence on voice

There were high statistically significant differences demonstrated among TVC regarding the history of some health conditions that could have an influence on voice quality. Teachers with history of repeated upper respiratory tract infections, nasal allergy, or chronic cough had reported to have more statistically significant voice complaints than those with no history of such health conditions. These results are shown in [Table 4].
Table 4: Distribution of health conditions among teachers with voice complaints (TVC).

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Risk factors of voice problems in teachers

OR and 95%CI were calculated for all the variables that could have an influence on voice to find out possible risk factors of voice problems in TVC. Variables that have been studied included: demographic characteristics, some living habits, teaching characteristics, and health condition. Female teachers were at a significantly higher risk of developing voice disorders than male teachers (OR= 2.48). Female teachers were about four times more frequent to have voice problems than male teachers. Teachers using loud voice were at significant higher risk for developing voice problems (OR= 2.11). Teachers who reported to use loud voice were about 2 times more likely to develop voice problems than those who are not raising their voices.

Also positive family history of voice disorders could be considered as a risk factor for having a voice-related problem in teachers. Teachers who reported positive family history of voice disorders were about 5 times more likely to have voice problems than those with negative family history (OR=4.96). These results are demonstrated in [Table 1].

The OR and 95%CI values regarding the teaching characteristics are demonstrated in table 2. Significantly higher risk of having voice problems was found in secondary and intermediate school teachers. Teachers in the secondary and intermediate schools were about 2 times more liable to have voice disorders than those in primary schools (OR= 2.16 and 2.14 respectively). Science teachers were at a significantly higher risk of developing voice problems than other teachers who teach other courses. Teachers who teach science were about 3 times more likely to get voice disorders than those who teach other courses. There was a significant higher risk for teachers who used to teach >30 students per class than those who teach <30 students. Teachers who teach >30 students/class were about 2 times more liable to have voice problems than others (OR=2.27). At the same time, teachers who reported history of repeated upper respiratory tract infection, nasal allergy or chronic cough had about 3-4 time higher risk to have voice problems than those who reported no history of such conditions (OR= 4.6, 2.98, and 4.27 respectively) [Table 4].

Other tested variables

[Table 5] demonstrates some other variables that have been tested in the study group, with the distribution of the frequency of these variables among the total sample of teachers who participated in the study.
Table 5: Distribution of health conditions among teachers with voice complaints (TVC).

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  Discussion Top


Although most of the studies about professional voice users include teachers as high risk occupational group to develop voice disorders, there is variable documented prevalence of voice problems in teachers. This is because still there is no reliable data on the incidence of dysphonia in the general population. Also within the profession, the degree of voice demand is highly variable [19].

This is the first study in the Kingdom of Saudi Arabia that investigates the voice problems in teachers and the risk factors of these problems. Thirty three percent of the teachers participated in this study reported to have a voice-related problem. This percent is close to that has been reported in previous related studies [2],[4],[6],[13],[14],[20]. In addition, there was high response rate (78%) among the teachers who participated in this study. This may indicate that most of the teachers do consider voice quality as an important factor that could have an impact on their teaching profession. Moreover, 90 % of teachers who participated in this study reported that voice care is important.

More male teachers participated in this study than female teachers. In other related studies, female teachers were the only [21] or the main participants [6],[22]. Moreover, more female teachers had reported having voice problems than male teachers. The difference was statistically highly significant. This coincides with the findings of Pekkarinen et al [1], smith et al [16], and Urrutikoetxea et al [23], who reported that voice problems were more prevalent in female teachers. This could be related to some peculiarities that women have which make them at more risk of developing voice problems, such as female glottic configuration favoring glottic bowing [24],[25], hormonal influence on vocal qualities, [26]higher incidence of endocrinological diseases, [27] and lower levels of hyaluronic acid in the superficial layers of lamina propria [28] Aging may further deteriorate vocal function [29],[30]. Although the sample size in our study was relatively enough, those effects were not seen in our population as there was no demonstrated significant difference between teachers with positive voice complaints regarding the age group. These findings match that of Chen et al. [7]. However, the relationship of age and voice problems in this study was inconsistent with Roy et al’s, [6] Smith et al’s, [4] and Russell et al’s [2] findings for American and Australian teachers, as they found a higher prevalence of voice problems in teachers older than 50 years. This indicates that more studies are needed to reveal the effect of age on the voice quality of teachers.

Because of physical differences in vocal physiology, people may need to work differently to avoid vocal problems during their career. In the current study, loud voice during conversations was the most prominent living habit that showed significant difference among teachers who reported to have voice complaints. Moreover, 15 % of teachers who participated in this study used their voices in extra-vocal activities in addition to teaching, e.g., as Imams in prayers. This emphasizes the importance of following vocal hygiene measures in teachers who want to keep their voice in optimal conditions.

It is generally accepted that familial voice characteristics are most likely combinations of genetic and environmental influences. However, it is still unknown to what extent which factor plays a larger role than the other. It may be that genetics predisposes to vocal fold tissue injury and when combined with a vocally demanding occupation, such as teaching, voice disorders may manifest [6]. The results of the current study showed that teachers with positive family history of voice problems are at more risk of developing voice disorders. Similar findings were also reported by Roy et al. [6] as they found in their study that family history of voice problems in teachers were positively associated with having voice disorders. These findings suggest that shared genes or environmental factors may contribute to voice vulnerability. However, further investigations exploring the relationship between family history and voice disorders are needed. Years of teaching experience have been always considered contributing to vocal dysfunction [31]. According to the findings reported by Marks [32] more experienced teachers were more prone to develop voice problems than others with less teaching experience. On the other hand, Mjaavatn [33] found that younger teachers reported greater vocal difficulties due to working longer hours and having poorer vocal hygiene techniques than their older and more experienced peers. However, in our study there was no significant differences between TVC based on their teaching experience. These results matched that of Sapir et al3 and Smith et al [17] who reported that teaching experience did not significantly influence the risk of reporting a voice problem.

Some studies suggested that the grade levels may have an influence on developing voice disorders in teachers. In their study, Unger and Bastian [34]suggested that teachers working with specific grade levels can be particularly susceptible to vocal problems. According to Sarfati, [31], primary teachers are more likely to develop voice problems than other teachers because of the excessive demands placed on the voice due to the dependence on oral rather than written communication when teaching young children. However, in our study teachers of secondary and intermediate schools were significantly more liable for developing voice problems than those in the primary schools. This may be explained by the system of “continuous evaluation” that is used in Saudi primary schools. This system is thought to require less vocal efforts from the teachers’ side in teaching and assessing primary school students. Few studies investigated the effect of the course given by teachers on their voice quality. Smith et al [17] found that physical education is one of the courses that has a significant influence on the voice of teachers. This was attributed to the high vocal demand needed in coaching such as yelling over a long distance without using amplification system. Also in the same study, they found that biology and chemistry courses were associated with a higher risk of having a voice problem. However, they could not find an explanation of that finding. In our study, science was the only course that carried a significant risk of developing voice problems in teachers. A possible reason is that science is considered one of the courses that contains large amount of scientific matter which needs much vocal effort from keen teachers to deliver such information to their students. The number of students in the class appears to have a significant impact on the voice quality in teaching. In the current study, teachers who used to teach larger number of students were at significantly higher risk than those who teach smaller numbers. This coincides with the finding of Preciado et al [35] and Urrutikoetxea et al [23] who reported that larger students’ numbers in the class is associated with increased frequency of voice disorders. This could be related to the excessive background noise in large classes that entails higher vocal demands by the teachers.

It is generally known that smoking has negative impacts on voice [23],[36]. However, smoking in this study did not appear to have a significant effect on the voice quality of teachers. These results coincide with that of Roy et al.[6] in their study of school teachers and with that of Miller and Verdolini [11] in their study of signing teachers. This might be explained by the assumed lower smoking habit in teachers compared to the general population.

The most commonly reported voice symptoms among teachers in this study were throat dryness, frequent throat clearing, and globus sensation. Moreover, 38 % of TVC reported that their voice problems were progressing and deteriorating. Among the teachers with history of voice disorders, those who reported the presence of these symptoms were significantly more than teachers who did not experience such manifestations. That was almost the same finding reported by other related studies [3],[16],[17],[22].

Some health conditions could have significant effect on voice and can be added to the factors that predispose to voice problems in teachers. In our study, teachers who reported to have history of repeated upper respiratory tract infection, nasal allergy, or chronic cough were significantly at higher risk for developing voice problems than those who did not report such problems. These findings match that of Roy et al [6] who reported that the frequency of voice disorders was significantly higher for those who experienced respiratory infections, allergies, asthma, colds, sinus infections, and postnasal drip.

The vocal condition of the teachers could have significant impact on the teaching profession. The results of this study showed that 13 % of the study sample reported absenteeism from school because of their voice problems. Moreover, 11 % of the participants thought of quitting the career of teaching because of the same reason. Similar findings were reported by Russell et al [2] , Sapir et al [3] and Smith et al, [17], who found that more than one-third of teachers with voice problems missed work as a result. This reflects the potential impact of voice problems on teachers and on the education profession.

Based on the results of this study, reduction or elimination of risk factors of voice disorders in teachers would be reflected on improving their vocal behavior which consequently will have a positive impact on the teaching profession as a whole. Preventive strategies and planned vocal hygiene programs for awareness and care of voice problems should be included in the education of future teachers as well as in the teaching process [2],[3],[6],[16],[37],[38]. These programs may include two types of prevention. Primary prevention which refers to elimination of any factor that might cause a voice disorder, while secondary prevention involves early detection and treatment of voice disorders [39]. The importance of this cannot be ignored, since only 24 % of the study sample reported that they are aware of vocal hygiene advices, 72 % stressed on the importance of vocal training before teaching, and 68 % of the participants mentioned that vocal difficulties during teaching should be considered as occupational disorders. In conclusion, the current study showed that there is a high prevalence of voice problems among Saudi teachers in Riyadh city (33%). There are many risk factors that could predispose to these problems. Some demographic variables like gender and family history of voice disorders could act as risk factors of such problems. Loud voice appears to have a significant impact on the voice quality of teachers. Teaching characteristics as well can contribute significantly to the development of voice problems in teachers. Future studies to evaluate the detailed effects of voice disorders in teachers on the teaching career are recommended.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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