Positioning of earphones and variations in auditory thresholds
Bettina Poggi Almeida1, Pedro de Lemos Menezes2, Kelly Cristina Lira de Andrade3
1Especialização em Fonoaudiologia do Trabalho, Universidade Estadual de Ciências da Saúde de Alagoas (UNCISAL), Marechal Deodoro, AL, Brazil.
Introduction:
One of the problems observed in pure-tone audiometry tonal has been the variation in test results of a same individual, particularly at frequencies of 4kHz, 6kHz and/or 8kHz. Improper placement of headphones is one of the factors that can cause alterations in results.
Objective:
To compare differences in auditory thresholds using earphones positioned by the examiner and by the worker.
Methods:
Clinical and experimental study conducted in 2009, with 324 workers aged between 19 and 61 years, with a mean of 33.29 years and mean exposure time of 7.67 years. All subjects were familiar with audiometry procedures. Auditory thresholds were obtained at frequencies of 0.25-8kHz, with earphones positioned by the examiners, and at frequencies of 4, 6 and 8kHz, with earphones placed by workers in a comfortable position, following the examiner's instructions. The thresholds obtained in these two situations were compared.
Results:
The three frequencies exhibited better responses with earphones placed by the workers themselves (p<0.001). At a frequency of 8kHz a greater difference was found (p<0.001), with a mean of 13.89dB and standard deviation of 6.07dB.
Conclusion:
Earphone placement by the workers themselves under supervision of the examiner results in improved mean auditory thresholds at frequencies of 4, 6 and 8kHz, the last one significantly higher than the other two.
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