The curve of intelligibility for the Freiburg mono-syllabic test in noise with fixed SNR of 5 dB

Objective Since years, the mono-syllabic Freiburg test (FBE) has been one of the most used tests for speech-audiometry in the German language. Sometimes ago, measurement of FBE with noise has been established additionally (FBE-S). This study investigates hearing in noise using the FBE at different levels and added noise 5 dB less.

Methods 60 normal hearing German native-speakers aged between 18 and 31 participated in the study. All measurements have been done at the military hospital of the German army in Hamburg in autumn 2018. Speech-intelligibility was measured in 5 dB steps by using one list of the FBE, presented from 10 to 95 dB and 5 dB less noise. Subsequently, the average of all intelligibility rates and confidence intervals (CI) were determined.

Results 9 female and 31 male subjects took part in the study. The average age was 24,32 years (±3,29 years). The analysis of variance for fixed effects demonstrated a high-significant dependency between the levels of sounds/ noise and the intelligibility of speech (p < 0.0001). The average values of intelligibility, the belonging 95% CI, and the frequency distribution have been presented both, by table and graphs.

Discussion Expectedly, the rate of intelligibility of the FBE-S is in comparison to the norm-curve of the FBE, less. The average values of the FBE-S are reaching the saturation area at a volume of 70/65 dB with an intelligibility rate of 90% (for comparison: the point of saturation of 100% intelligibility of the FBE without noise is reached at 55 dB). Using the averaged values of the FBE-S, individual results without and with hearing aids could better be interpreted. In the future, it could make sense to measure the benefit of hearing aids in noise at lower levels than today.

Poster-PDF A-1115.PDF

Publication History

Article published online:
10 June 2020