Development and validation of an automatic speech-in-noise screening test by telephone

To meet the need for an objective self-test for hearing screening, a new Dutch speech-in-noise test was developed. Digit triplets were used as speech material. The test was made fully automatic, was controlled by a computer, and can be done by telephone. It measures the speech reception threshold (triplet SRT_n) using an adaptive procedure, in about 3 min. Our experiments showed no significant influence of telephone type or listening environment. Measurement errors were within 1 dB, which makes the test accurate. In additional experiments with hearing-impaired subjects (76 ears of 38 listeners), the new test was compared to the existing sentence SRT_n test of Plomp and Mimpen, which is considered to be the standard. The correlation between both SRT_ns was 0.866. As expected, correlations between the triplet SRT_n test by telephone and average pure-tone thresholds are somewhat lower: 0.732 for PTA_0.5.1.2, and 0.770 for PTA _0.5.1.2.4. When proper SRT_n values were chosen for distinguishing between normal-hearing and hearing-impaired subjects, the triplet SRT_n test was found to have a sensitivity of 0.91 and a specificity of 0.93.