Causes and consequences of voice disorders among teachers

Abstract

Voice disorders are a major problem among teachers. However, the reported prevalence of these disorders have a wide range, and the natural variation of voice disorders among teachers is unknown due to the lack of longitudinal studies. Moreover, there is not a consensus about the best approach for assessing voice disorders among teachers at work. Results on prevalence of voice disorders in this occupational group are based on different sources (questionnaires, perceptual assessment, clinical assessment, acoustical assessment), which make difficult the comparison of these results. On the other hand, associated factors of voice disorders among teachers include individual factors, such as sex and age; and work-related conditions, such as acoustic and noise conditions, topic of teaching and using loud voice. Yet, there is a lack of knowledge regarding the determinants of voice disorders among teachers. In addition, voice disorders have a big impact on quality of life and daily performance of teachers. Moreover, voice disorders may interfere with the productivity at work, and thus generate economic costs to the schools and the teachers due to the voice-related absenteeism, reduction in productivity at work, and use of health services.

This thesis focuses on the occurrence, causes and consequences of voice disorders among teachers with four aims: 1. To assess the presence of voice disorders among teachers. 2. To evaluate the agreement between different methods of assessment of voice disorders among teachers. 3. To distinguish work-related determinants of voice disorders among teachers. 4. To identify the socio-economic consequences of voice disorders among teachers. The main results of this thesis were: 1. Teachers had a significantly increased occurrence of voice disorders compared with other occupations. 2. Self-report of voice complaints, perceptual assessment of voice and objective assessment of voice show large differences and may offer different information about voice quality and functioning. Therefore, it is recommended to include in the assessment of work-related voice disorders information concerning these three assessment methods. 3. Noise and acoustics might play a role in the occurrence of voice symptoms among teachers. Therefore, it is advisable to include physical measurements of the working environment in studies that measure the impact of noise and acoustics on vocal health. 4. The increase on health care use, absenteeism, and productivity loss at work due to voice disorders among teachers represent an important burden of these disorders.