Acceptable noise level: Repeatability with Danish and non-semantic speech materials for adults with normal hearing

OBJECTIVE: The acceptable noise level (ANL) is used to quantify the amount of background noise that subjects can accept while listening to speech, and is suggested for prediction of individual hearing-aid use. The aim of this study was to assess the repeatability of the ANL measured in normal-hearing subjects using running Danish and non-semantic speech materials as stimuli and modulated speech-spectrum and multi-talker babble noises as competing stimuli. DESIGN: ANL was measured in both ears at two test sessions separated by a period ranging from 12 to 77 days. At each session the measurements at the first and the second ear were separated in time by 15-30 minutes. Bland-Altman plots and calculation of the coefficient of repeatability (CR) were used to estimate the repeatability. STUDY SAMPLE: Thirty nine normal-hearing subjects. RESULTS: The ANL CR was 6.0-8.9 dB for repeated tests separated by about 15-30 minutes and 7.2-10.2 dB for repeated tests separated by 12 days or more. CONCLUSIONS: The ANL test has poor repeatability when assessed with Danish and non-semantic speech materials on normal-hearing subjects. The same CR among hearing-impaired subjects would imply too poor repeatability to predict individual patterns of future hearing-aid use.