CLINICAL-TRIAL OF A DIGITAL HEARING-AID

A clinical trial of the Oticon DigiFocus hearing aid was performed. Th e test aid was evaluated on 33 subjects with several years experience as users of modem analog hearing aids. These aids were used as referen ce for the 1-month-long trial. The Abbreviated Profile of Hearing Aid Benefit (APHAB) showed a mean difference in benefit with superior rati ngs for the test aid concerning ease of communication, speech in rever beration and speech in background noise. The subjects' own aids were r ated somewhat better concerning aversiveness of sounds, but this diffe rence was not statistically significant. The Gothenburg Profile showed a statistically significant difference between the test aid and the r eference aids in favour of the test aid. The difference was most evide nt with regard to speech communication and the effects of hearing loss on social interactions. Sound quality ratings concerning clearness we re significantly higher for the test aid. Speech recognition threshold s in noise were on average 0.7 dB better for the test aids when tested at speech levels 60 and 75 dB. The difference was statistically signi ficant only at 75 dB. There was a significant interaction between gene ral preference and hearing aid type, indicating that overall sound qua lity was an important factor affecting the general preference for eith er the test aid or the reference aid. Twenty-three subjects generally preferred the test aid, six preferred their own aid and four stated no difference.