Adaptation of scoring methods for testing cochlear implant users using the Cantonese Hearing In Noise Test (CHINT)

It is often difficult to use an adaptive approach to evaluate speech reception in noise in cochlear implant (CI) users, because of variations in performance. Thus, two studies were conducted to develop an alternative method for scoring the Cantonese Hearing In Noise Test (CHINT) and to use this method for evaluating speech reception in CI users.

In Study 1, 20 normal-hearing adults were tested using four scoring methods, including three modified and the standard HINT scoring method. The speech was presented in the front, and noise originated from the front, the right, or the left loudspeakers, as a standard HINT protocol. Threshold signal-to-noise ratio (S/N) and word intelligibility percent score (word score) were measured in each CHINT noise condition using each rule. In Study 2, depending on the word score of the individual CI user in the quiet CHINT condition, different adaptive rules were selected to score the responses from 12 CI users in the three noise conditions. The percentage of CI users who could successfully be tested using these scoring methods was evaluated.

In Study 1, threshold S/Ns obtained using different rules were significantly different and consistent with expectations. The slopes of the performance-intensity function relating mean word scores and threshold S/Ns were linear and agreed well with previous findings. These results showed that the modified rules could be used to adaptively measure CHINT thresholds in noise. In Study 2, these modified rules were successful in measuring CHINT thresholds in 10 of the 12 participants, whose word scores in quiet exceeded 40%.

These modified rules could be used in CI users whose speech reception ability could not have been measured otherwise.