Repeatability, agreement, and feasibility of using the threshold equalizing noise test and fast psychophysical tuning curves in a clinical setting.

OBJECTIVE: To investigate repeatability, agreement, and clinical feasibility of the threshold equalizing noise (TEN) test and fast psychophysical tuning curve (PTC) measurements to detect off-frequency listening, an indicator of cochlear dead regions (DRs).

DESIGN: The TEN-test was carried out from 0.5 to 4 kHz and fast PTCs were carried out at ≥ 2 frequencies.

STUDY SAMPLE: The TEN-test was completed on 70 ears; fast PTCs were measured on 20 ears.

RESULTS: TEN-test findings were repeatable in terms of meeting the criteria for a DR (97%) and identifying the same edge frequency (fe) (87%). In all cases, fast PTCs were repeatable in terms of meeting the criteria for DRs. There was 87% agreement between the two procedures in terms of the presence of off-frequency listening, and there was 73% agreement in terms of fe. Fast PTCs had a 10% lower 'conclusive finding' rate than the TEN-test and the test duration was typically 40 minutes longer.

CONCLUSIONS: Both the TEN-test and fast PTCs have high test-retest repeatability. The TEN-test is more clinically feasible due to its shorter test duration and higher interpretation rate, but it may underestimate the extent of a DR because of its inability to precisely identify fe.