Time-Compressed Speech in the Auditory Processing Evaluation

Nova Southeastern University, Davie, Florida, USA

Objective: Examine the internal validity of the time-compressed PBK and NU-6 word lists in a pediatric population seen for clinical auditory processing evaluations (APEs). Background: Temporal alterations to speech stimuli are used to assess a listeners’ ability to process information when acoustical redundancy is minimized (i.e., monaural low redundancy). Two time-compressed tests used with adolescents include the PBK and NU-6. Anomalous patterns of results were observed during data analysis within a larger chart review research project, which provoked a closer evaluation of the time-compressed PBK and NU-6 test results. Methods: Retrospective chart review of over 100 APEs completed in the NSU Audiology clinic from July 2012 to July 2017. Data extracted from electronic medical records included results from the test battery, diagnosis, and individual subject responses from scans of the original score sheets Results: In total, 242 individual half-lists were run (PBK= 114). Data analysis revealed that the lists were not equivalent within the individual compression ratios; average List 1 scores were significantly higher than average List 3 scores for both the PBK and NU-6, independent of compression ratio. Further, the NU-6 word lists were determined to have significant ceiling effects. The average scores were different from the results published when the lists were developed: average NU-6 scores are considerably higher than average scores originally published by Beasley and colleagues (1972). Conclusion: Significant technical issues were found in both the compressed versions of the PBK and NU-6 lists suggest these measures may not be appropriate for use in clinical APEs.