Voice Complaints among Public Transport Workers in the Metropolitan Region of Belo Horizonte, Brazil

Abstract

Objective: To investigate the prevalence of voice complaints among bus transport workers in a metropolitan area in Brazil and examine whether sociodemographic and occupational factors were associated with this outcome. This study is part of a larger study that investigated the working conditions and health of drivers and conductors of urban transportation. Methods: The sample size (1,607 participants) was calculated by means of quotas and was stratified according to occupation (drivers and conductors) in the bus companies of Belo Horizonte, Betim and Contagem. Face-to-face interviews were facilitated by means of a digital questionnaire, applied by the interviewer using a netbook. The outcome variable was constructed from combining the responses to the following two questions: (1) Over the last two weeks, have you felt tired when speaking? (no/sometimes/every day). (2) Over the last two weeks, have you noticed any worsening of your voice quality? (no/sometimes/every day). Sociodemographic, lifestyle, occupational characteristic and health situation data were gathered. Results: The prevalence found was 29% overall: 24% for drivers and 34% for conductors. Attention was drawn to positive associations with the function of conductor and with reports of exposure to vibration and thermal discomfort. Among the individual factors, only female gender reached statistical significance. Conclusion: Risk factors exist that justify interventions to promote voice health within the urban transport sector under study. It would be appropriate to investigate whether vibration of the whole body would influence the functioning and morphology of the larynx.