Estimation of client-assessed hearing aid performance based upon unaided variables.

The purpose of this study was to investigate the possibility of estimating client-assessed hearing aid performance before hearing aids are purchased. Aided performance was represented by the Profile of Hearing Aid Performance (PHAP, Cox & Gilmore, 1990). Multiple regression was applied to 16 unaided predictor variables and to 8 response variables. The response variables were the scores from the seven PHAP subscales plus the overall PHAP score, which were obtained from 46 participants. Audiologic, demographic, and psychological information was included among the 16 predictor variables. The average widths of 95% prediction intervals showed that, with the exception of the Aversiveness of Sounds and Ease of Communication subscales, PHAP subscale scores were predicted within 15% on average. Eighty percent or more of the individual participants' PHAP scores were predicted within 15% for all but the Aversiveness of Sounds subscale. The predictor variables appearing in regression equations for the greatest number of PHAP subscales include age, Communication Strategies and Personal Adjustment scores from the Communication Profile for the Hearing Impaired (Demorest & Erdman, 1986), Revised Speech Perception in Noise (Bilger, Neutzel, Rabinowitz, & Rzeczkowski, 1984; Kalikow, Stevens, & Elliott, 1977) test scores, comfortable loudness levels, and the difference between National Acoustic Laboratories' target gain (Byrne & Dillon, 1986) and actual insertion gain. Further testing of the models on additional participants would be needed to determine their clinical applicability. In addition to being potentially useful for predicting client-assessed aided performance, the equations obtained in this study identify relationships between the aided and unaided variables that can be applied in the counseling of new hearing aid users.