The Audibility of Low Vision Devices with Speech Output Used by Older Adults with Dual Sensory Impairment

SIGNIFICANCE: The successful uptake, integration, and use of vision rehabilitation devices with speech output depend to a large part on their audibility. However, individuals with combined vision and hearing impairments are at a disadvantage when using devices that do not consider multiple impairments. PURPOSE: Sensory rehabilitation for individuals with combined vision and hearing impairment often relies on the use of assistive technology devices that use speech outputs (e.g., talking clock), but in individuals with dual impairment, their use is likely compromised by a concurrent hearing loss. The goal of this study was to evaluate the audibility of these devices in a population of individuals with acquired dual sensory impairment. METHODS: We measured the ability to correctly repeat speech output presented by three assistive technology devices (talking watch, calculator, scanner) and confidence levels in response accuracy in 24 participants with visual impairment only and in 22 individuals with dual sensory loss. Stimuli were presented at three volumes that were repeated one or four times. Participants were placed at a fixed distance of 74 cm from the sound source. RESULTS: The pattern of results was similar across the different devices, whereby an interaction of volume and repetition indicated that participants' accuracy to repeat a phrase and their confidence in their response improved with increasing volume, but more so at higher numbers of repetition (P < .05; ω(2), from 0.005 to 0.298). Participants with dual sensory loss generally had lower accuracy and confidence. CONCLUSIONS: Scores and confidence levels being very low across devices and users suggest that even participants with normal hearing for their age experienced a certain level of difficulty understanding speech output, confirming the need for better assistive technology device design.