Purpose: The purpose of this study was to evaluate the efficacy of selected speech amplification devices in individuals with hypophonia and idiopathic Parkinson's disease (PD).
Method: This study compared the effectiveness of seven devices (ADDvox, BoomVox, ChatterVox, Oticon Amigo, SoniVox, Spokeman, and Voicette) to unamplified speech for 11 participants with PD during conversation in 65-dB SPL multitalker noise, using experience ratings collected from participant questionnaires and speech performance measures (i.e., speech-to-noise ratio [SNR], speech intensity, and intelligibility) obtained from audio recordings.
Results: Compared with unamplified speech, device use increased SNR by 1.07-4.73 dB SPL and speech intensity by 1.1-5.1 dB SPL, and it significantly increased transcribed intelligibility from 13.8% to 58.9%. In addition, the type of device used significantly affected speech performance measures (e.g., BoomVox was significantly higher than most of the other devices for SNR, speech intensity, and intelligibility). However, experience ratings did not always correspond to performance measures.
Conclusions: This study found preliminary evidence of improved speech performance with device use for individuals with PD. A tentative hierarchy is suggested for device recommendations. Future research is needed to determine which measures will predict long-term device acceptance in PD.