Effective Identification of Functional Hearing Loss Using Behavioral Threshold Measures

Abstract

Purpose Four functional hearing loss protocols were evaluated. Method For each protocol, 30 participants feigned a hearing loss first on an audiogram and then for a screening test that began a threshold search from extreme levels (–10 or 90 dB HL). Two-tone and 3-tone protocols compared thresholds for ascending and descending tones for 2 (0.5 and 1.0 kHz) and 3 (0.5, 1.0, and 2.0 kHz) frequencies, respectively. A noise-band protocol compared an ascending noise-band threshold with that for 2 descending tones (0.5 and 1.0 kHz). A spondee protocol compared an ascending spondee threshold with that for 2 descending tones (0.5 and 1.0 kHz). These measures were repeated without the participants feigning losses. Results With nonfeigning participants, ascending and descending threshold differences were minimal for all protocols. When the participants feigned a loss, the spondee protocol produced the largest average threshold difference (30.8 dB), whereas the other protocols produced smaller differences (19.6–22.2 dB). Conclusions Using both the screening test and a comparison of the initial audiogram with the screening test, the spondee and 3-tone protocols resulted in 100% true positives and 0% false positives for functional hearing loss. Either of these protocols could be used clinically or in occupational hearing conservation programs.