A Factor Analysis of Competing Message Testing in Hearing Aid Evaluations

Abstract

Retrospective data compiled from routine clinical hearing aid evaluations were examined to identify the primary factors influencing test performance of hearing-impaired listeners. Results were analyzed from representative and similarly conducted evaluations with 68 patients. Unaided test measurements were obtained bilaterally, and included pure-tone thresholds, slope of the audiometric contour, speech reception thresholds (SRT), and speech discrimination scores. Aided tests included speech reception threshold, speech discrimination in quiet, and speech discrimination against a competing message. When intercorrelations among 27 test variables were subjected to factor analysis, five factors emerged: speech discrimination, nontest ear thresholds, unaided sensitivity-test ear, interear high frequency thresholds, and aided SRT. The 68 sets of data were subdivided into two groups on the basis of severity of hearing impairment, and new factor analysis were run. Here the same array of factors emerged with the addition of (1) a nontest ear high-frequency factor for the milder loss subgroup and (2) two factors designated as SRT—poorest aided performance, and discrimination—poorest aided performance for the greater loss subgroup.