Population study of the ability to benefit from amplification and the provision of a hearing aid in 55-74-year-old first-time hearing aid users.

About 40% of 55-74-year-olds have an impairment in at least one ear of 25+ dB HL, and 27% have bilateral impairment at this level, with 11% being impaired bilaterally at 35+ dB HL. Only 6% currently use a hearing aid. The performance of a random sample of participants aged 55-74 years on speech-in-noise tasks shows that significant statistical benefit was obtained from bilateral amplification in over 20% of the population who do not currently use a hearing aid. The offer of a hearing aid to all those who exceeded a 25 dB HL criterion in the worse car was accepted and taken up by 40%, with 16% declining and the remainder being excluded for pathological and logistic reasons (e.g. hearing loss profile not suitable for aid). This is a very high rate of 71% acceptance. One in four fitted with the hearing aid showed a statistical advantage for hearing speech in noise in freefield (noise and speech from in front) with the hearing aid. Thus at least 10% of the population who do not currently use an aid would benefit substantially from a hearing aid in a quiet speech-in-noise environment. Those with poorer cognitive function show greater benefit overall and less disadvantage in very bad signal-to-noise environments. The overall pattern of results support screening and providing hearing aids to those who do not currently have an aid(s), and suggests that there would be considerable population benefit. At least two main questions for further research remain: (1) would bilateral aiding strategies give greater benefit; and (2) would different hearing aids and fitting strategies be more appropriate for people with differing 'cognitive task' loadings on phonological memory and lexical decision factors?