Telephone listening ability for hearing-impaired individuals.

Forty-five subjects with bilateral sensorineural hearing losses were divided into three groups (N = 15/group) based on the audiometric configuration of their test ear. The subjects were evaluated in three listening conditions by assessing their word discrimination ability by presenting stimuli at 86 dB SPL (simulating the output of a standard telephone handset ) and most comfortable loudness (MCL) (simulating the output of a telephone amplifier handset ). The three listening conditions were TDH-39 earphone, unaided telephone, and aided telephone with their personal hearing aid acoustically coupled to a telephone handset . Results indicated that subjects with precipitous hearing losses had similar word discrimination scores for all three listening conditions at 86 dB SPL and MCL. Subjects with gradual slope or flat hearing losses had similar word discrimination scores with a TDH-39 earphone, unaided telephone, and their hearing aids acoustically coupled to a telephone handset at 86 dB SPL. The subjects with gradual slope or flat losses also had similar word discrimination scores across the listening modes at MCL, but they had better word discrimination scores in all listening modes when the word lists were presented at MCL compared with 86 dB SPL.