Date of Award
Doctor of Philosophy
Speech and Hearing Science
Igor V. Nabelek
Anna Nabelek, Samuel Burchfield, Esteban Walker
The purpose of this study was to determine if client-assessed hearing aid performance, usage, and satisfaction ratings could be predicted before hearing aids are purchased. Aided performance was represented by the Profile of Hearing Aid Performance, (PHAP, Cox and Gilmore, 1990), subscales. Based upon data from 46 subjects, multiple regression was applied to 16 unaided variables to determine if they could be used to predict the response variables of performance, usage and satisfaction. The 16 unaided variables included pure tone average, slope of hearing loss, the Speech Perception in Noise (SPIN) test (Kalikow, Stevens & Elliott, 1977), dynamic range, comfortable loudness level, tolerated signal-to-noise levels for babble and speech spectrum noise, the difference between actual gain and target gain based upon the National Acoustic Laboratories' prescription formula, age, gender, percentage of employment, years of education, number of medications taken, Personal Adjustment and Communication Strategies scores of the Communication Profile for the Hearing Impaired (Demorest and Erdman, 1986), and motivation for pursuing hearing aid use.
The regression equations obtained for the Familiar Talkers, Background Noise and Reduced Cues subscales resulted in predicted values which matched actual scores within 12% for about 75% of the subjects. The equation for usage estimated hours of daily hearing aid use within three hours for 75% of the subjects. Further testing of these models using other subjects would be needed to determine the clinical applicability of these equations. Estimates of the other subscale scores were not accurate enough to be considered for clinical application. However, the equations identified relationships between the aided and unaided variables which may be useful for counseling new hearing aid users. Scores for most of the PHAP sub scales and for hours of hearing aid use were found to be related to age, Personal Adjustment scores and SPIN scores. Comfortable loudness levels, Communication Strategies scores and difference between insertion gain and NAL target gain were found to be partially predictive of performance but not of usage or satisfaction. Tolerated signal-to-noise levels were partially predictive of hearing aid usage and satisfaction, and percentage of time employed was related to usage.
Crowley, Hilary J., "Unaided Factors Predicting Client-Assessed Hearing Aid Performance, Usage and Satisfaction. " PhD diss., University of Tennessee, 1994.