Pure tone audiograms from hearing-impaired children. I. A statistical approach to summarizing audiogram information

Principal component analyses of the better-ear pure-tone audiograms from 201 hearing-impaired children are reported. The analyses show that two components, one measuring degree of hearing loss, the other the slope of the audiogram, account for 86% of the total variability. Two indices are proposed which correspond to the two components, but which have numerically simple coefficients and which, unlike the raw components, are perfectly "clean" measures of the two variables. Since these indices, 11 and 12, still account for 84% of the total audiogram variability, it is suggested that they may provide a quantitative basis for summarizing pure tone audiograms for general use.