Influence of environmental factors on hearing aid microphone preference.

The purpose of this study was to identify characteristics of everyday listening situations that influence user preferences for omnidirectional versus directional hearing aid microphones. Eleven experienced hearing aid users were fitted with digital hearing aids featuring switchable omnidirectional (OMNI) and adaptive-directional (DIR) modes (programs). For 6 weeks, their task was to identify and describe at least one listening situation each day in which one program performed better than the other using a checklist daily journal format. All participants reported difficulty identifying situations in which they could perceive a difference between the two microphone modes. Although an equal number had been requested, descriptions favoring the DIR outnumbered those for the OMNI. Chi-square tests were used to compare the distributions of 60 descriptions favoring the OMNI and 155 favoring the DIR across variables associated with the primary talker to whom the hearing aid user was listening, background noise, and other environmental characteristics. The results indicated that location of the primary talker, presence or absence and type of background noise, and type of space in which the communication occurred influenced microphone choice.