A comparison of speech discrimination scores by using PB-50 lists and the speech discrimination scale with hearing-impaired adults.

Performance-intensity functions were drawn for each of the 5 progressively more difficult 8-word subtests of Gaeth's Speech Discrimination Scale (SDS) with 16 limited-hearing Ss aged 20-88 yrs. Prior examination with the NU-6 test at 24 db SL revealed speech discrimination ability groupings, unrelated either to pure-tone ac hearing losses or to age. The largest (middle) group achieved scored of 50%-correct at -5, 0, 11, and 14 db SL (re pure-tone ac HTL averaged for the better 2 of the frequencies .5, 1, and 2 kc/s) for the subtests Digits, Easy Letters, Easy Words and Hard Letters respectively, as compared with 30 db SL for full PB lists; and never achieved 50%-correct for the Hard Words subtest. The possibility was suggested that the clinician might initiate speech testing with the East Words subtest and proceed to either more or less difficult subtests/levels as S responds. Each item would contain more statistical power than a single item in a 50-word PB list at a single SL.