Development and validation of the Leuven intelligibility sentence test with male speaker (LIST-m)

In addition to the LIST with a female speaker ( van Wieringen & Wouters, 2008 ), a new speech perception test with a male voice was developed and validated, for evaluating the intelligibility performance of cochlear implant (CI) users or severely hearing-impaired persons.

Three experimental steps were carried out: (1) a perceptual optimization of the recorded materials, (2) an evaluation in normal-hearing (NH) listeners, and (3) a validation in CI-users. Measurements were performed both in quiet and in noise.

Forty-four NH subjects and six CI-users participated.

After selecting the sentences with a similar intelligibility, the reference psychometric curve for NH listeners was determined, showing steep slopes for measurements in quiet (12.3%/dB) and in noise (18.7%/dB), similar to the LIST with female voice. The 38 lists of 10 sentences yielded equal scores, and the within-subject test-retest reliability was high (1.7 dB in quiet, 1.1 dB in noise). For the CI-users, parallel psychometric curves were found between the LIST with male and female voice.

The LIST-m is a reliable and valid speech intelligibility test that can be used for CI-users, both in quiet and in noise.