An investigation of list equivalency of the northwestern university auditory test no. 6 in interrupted broadband noise

The equivalency of Lists 1 to 4 of the Northwestern University Auditory Test No. 6 (NU-6; T. W. Tillman and R. Carhart, 1966) was investigated in interrupted broadband noise. Forty-eight young adults with normal hearing participated. All lists were administered at 50 dB sensation level re: listener spondee recognition thresholds at signal-to-noise ratios (S/Ns) of 10, 5, 0, -5, -10, -15, -20, -25, and -30 dB. Significant differences in listener performance were observed only at S/Ns ranging from 10 to -10. Significant mean list differences varied from 5.8% to 12.0%. These findings support the notion that caution should be exercised in the interpretation of listener performance differences with NU-6 stimuli presented in a background of interrupted noise.