Subjective Appraisal and Objective Assessment of the Hearing of Speech Amongst a Group of Adults with Impaired Hearing

Abstract

A number of patients with impaired hearing consulting the E.N.T. Dept. of Rikshospitalet were asked to appraise their hearing from a general point of view, and their hearing for speech in specified listening conditions. Data from 166 patients with median age 55 years, coming from all parts of Norway, representing 61 different occupations, with hearing loss within a range of 20 dB at 500 through 2000 Hz, and full discrimination on PB word lists, were selected. Good agreement existed between general appraisal and the sum of ratings for specified listening conditions. 37 per cent of the material rated their hearing as mediocre, 63 per cent as poor. As to hearing threshold for speech considerable overlapping existed between groups. Significant differences of threshold levels between ears increased, small ones reduced the difficulties caused by the same hearing loss for speech in the better ear. Hearing threshold level for speech in better and worse ear was 35 dB and 45 dB in the mediocre, 45 dB and 60 dB in the poor hearing group. Good agreement existed between threshold level for speech and for pure tones at 500 through 2000 Hz. Clinical conversational voice test was of no value in the individual case, but median values of the material give information on the relation of hearing loss to hearing distance for speech.

35 dB hearing loss for speech, or Hearing Index 64, is proposed as lower limit for procuring of a hearing aid free of charge according to present Norwegian regulations.