Further Evaluation of a Protocol for Integrated Speech Audiometry

When a bilateral evaluation is conducted with the integrated speech protocol described in Punch and Rakerd (2019), testing for the first ear concludes with a measurement of the uncomfortable loudness level for speech (UCL). The purpose of this study was to assess the possibility that exposure to the high speech intensities required for that UCL test might bias the subsequent measurement of a listener's most comfortable loudness level for speech (MCL) in the opposite ear.

Across 32 test runs, the left and right ear MCLs were established for 16 young adult listeners with normal hearing (five women, 11 men). The MCL assessed on each test run was measured twice. The first measurement was made at the start of the run and before a full integrated speech evaluation was conducted in the opposite ear (pretest); the second was made after that evaluation (posttest).

The difference between the MCL means measured on the pretest (37.7 dB) and the posttest (38.5 dB) was less than 1 dB, and it did not approach statistical significance, t(15) = 0.69, p = .50.

There was no evidence that UCL testing done in one ear on a bilateral speech test will have carryover effects that bias the subsequent measurement of a listener's MCL in the other ear. The results, therefore, support the potential clinical use of an integrated protocol when conducting bilateral speech audiometric evaluations.