Abstract
In Japan hearing aids (HAs) are categorized as medical devices, while personal listening devices (PLDs) are categorized as home appliances. The aim of this study was to compare the frequency characteristics and perform, objective and subjective evaluations of 2 HAs and 2 PLDs. Monosyllable intelligibility scores under noise was used as the objective parameter for evaluation and impression of sentences under noise was used as the subjective parameter. A total of 35, 15younger individuals (20 to 22 years old) with normal hearing and 20older individuals (41 to 55 years old) with normal hearing were enrolled in the study.
The study revealed that the frequency characteristics of the PLDs did not allow sufficient amplification of speech and showed an output of more than 100 dB SPL, indicating that use of PLDs may be associated with the risk of noise-induced hearing-loss. As for the HAs, sufficient amplification of speech was confirmed. In addition, it was considered that use of HAs would be associated with a low risk of noise-induced hearing-loss due to the output suppression control system.
The objective evaluation revealed significantly better result for the HAs than for the PLDs, whereas subjective evaluation yielded better results for the PLDs than for the HAs. HAs allowed better speech perception, although the hearing impression was poor. On the other hand, the hearing impression was better for the PLDs, even though monosyllable intelligibility was poorer.
