Speech-in-noise screening tests by internet, part 2: improving test sensitivity for noise-induced hearing loss.

OBJECTIVE: An easily accessible screening test can be valuable in the prevention of noise-induced hearing loss (NIHL). The Dutch National Hearing Foundation developed 'Earcheck', an internet-based speech-in-noise test, presenting CVC-words in stationary broadband noise. However, its sensitivity to detect NIHL appeared to be low, 51% ( Leensen et al, 2011 , part 1). The aim of the current study is to examine ways to improve Earcheck's sensitivity for (early) NIHL using different forms of noise filtering. DESIGN: The test's stationary broadband masking noise is replaced by six alternatives, including noises that have been temporally modulated, spectrally filtered by high-pass or low-pass filters, and combinations of temporal modulation and spectral filtering. STUDY SAMPLE: In this multi-centre study, 49 normal-hearing and 49 subjects with different degrees of NIHL participated. RESULTS: Hearing-impaired subjects deviated more clearly from normal performance when executing the test with alternative masking noises, except for the high-pass filtered conditions. Earcheck with low-pass filtered noise made the best distinction between normal hearing and NIHL, without reducing test reliability. The use of this noise condition improved the sensitivity of Earcheck to 95%. CONCLUSION: The use of low-pass filtered masking noise makes speech-in-noise tests more sensitive to detect NIHL in an early stage