Interlist equivalency of the Northwestern University Auditory Test No. 6 in quiet and noise with adult hearing-impaired individuals.

Abstract

The purpose of the study was to determine the influence of sensorineural hearing loss and broadband noise on the interlist equivalency of the Northwestern University Auditory Test No. 6 (NU-6). There were two groups of participants: the first group consisted of 14 adults with mild-to-moderate hearing loss (mean age = 56 years; SD = 4.83); the second group consisted of 11 age-matched, normal-hearing individuals (mean age = 55 years; SD = 4.69). Each group heard the four lists of the NU-6 in quiet and in broadband noise at four signal-to-noise ratios (-10 dB, -5 dB, 0 dB, and +5 dB). The NU-6 stimuli were presented at 35-dB sensation level relative to each listener's speech reception threshold. Results indicated that, for both groups, there was a significant main effect for NU-6 list. Post hoc single degree of freedom contrasts revealed that this main effect was due to significant differences between some of the lists when presented in background noise. There were no differences between the lists in quiet. Because of the findings of differences between some of the lists in noise, the authors suggested that clinicians or researchers use caution when comparing scores obtained from two different NU-6 lists over time. That is, if scores from two lists are different, it is important for the clinician to determine whether this disparity is due to a change in word recognition ability or simply due to a difference between the lists.