Impact of compression and hearing aid style on directional hearing aid benefit and performance.
OBJECTIVE
To evaluate the impact of low-threshold compression and hearing aid style (in-the-ear [ITE] versus behind-the-ear [BTE]) on the directional benefit and performance of commercially available directional hearing aids.


METHODS
Forty-seven adult listeners with mild-to-moderate sensorineural hearing loss were fit bilaterally with one BTE and four different ITE hearing aids. Speech recognition performance was measured through the Connected Speech Test (CST) and Hearing in Noise Test (HINT) for a simulated noisy restaurant environment.


RESULTS
For both the HINT and CST, speech recognition performance was significantly greater for subjects fit with directional in comparison with omnidirectional microphone hearing aids. Performance was significantly poorer for the BTE instrument in comparison with the ITE hearing aids when using omnidirectional microphones. No differences were found for directional benefit between compression and linear fitting schemes.


CONCLUSIONS
No systematic relationship was found between the relative directional benefit and hearing aid style; however, the speech recognition performance of the subjects was somewhat predictable based on Directivity Index measures of the individual hearing aid models. The fact that compression did not interact significantly with microphone type agrees well with previously reported electroacoustic data.
Ricketts
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Dan Maddox Hearing Aid Research Laboratory, Vanderbilt Bill Wilkerson Center, Nashville, Tennessee 37212, USA.
Lindley
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Henry
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D000161:Acoustic Stimulation / Q000295:instrumentation; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004777:Environment; D004867:Equipment Design; D006310:Hearing Aids; D006319:Hearing Loss, Sensorineural / Q000534:rehabilitation*; D006801:Humans; D008875:Middle Aged; D017755:Prosthesis Fitting; D012720:Severity of Illness Index; D013067:Speech Perception; D013069:Speech Reception Threshold Test; D013997:Time Factors