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Voice amplifier: effects on dose and vocal intensity of teachers without dysphonia
Evelyn Vanessa Silva Souza1, Iara Barreto Bassi2, Ana Cristina Côrtes Gama3
1Programa de Pós-graduação em Ciências Fonoaudiológicas, Departamento de Fonoaudiologia, Faculdade de Medicina, Universidade Federal de Minas Gerais - UFMG - Belo Horizonte (MG), Brasil.
Purpose:
Analyze the interference of using the voice amplifier in vocal dose of non-dysphonic teachers.
Methods:
This is an experimental study comparing people from the same ambience compound for 20 teachers from municipal elementary school in Belo Horizonte/MG. After consent, the participants were requested to answer the vocal symptom scale questionnaire (ESV) and later participated in two different moments of the study, for which they randomly selected. In the first moment, the participants used only the vocal dosimeter and in the second, they used the vocal dosimeter and the voice amplifier. The measurements were recorded by the device for 1h40m, in the classroom that the teachers taught. The time between the two measurements was one week, with the same room, the same time and the same discipline being taught, at both times.
Results:
The intensity parameter was the only one that showed difference with the use of the voice amplifier.
Conclusion:
Use voice amplification while non-dysphonic teachers are teaching doesn't affect the fundamental frequency and vocal dose measure in the acoustics parameters. The vocal intensity is smaller when teacher uses the vocal amplification.
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