Audiologic Assessment, Hearing Loss, and Aural Rehabilitation
Domain 4 tests audiogram interpretation, hearing loss classification, screening versus diagnosis, and aural rehabilitation. Expect questions on air and bone conduction, masking, speech recognition, hearing aids, cochlear implants, and communication strategies.
Core rules
- Conductive hearing loss shows reduced air-conduction thresholds with normal or near-normal bone conduction and an air-bone gap. Sensorineural loss affects both air and bone without a significant gap. Mixed loss shows both.
- Common adult degree labels are mild 26–40 dB HL, moderate 41–55, moderately severe 56–70, severe 71–90, and profound above 90 dB HL. Use the appropriate pediatric or clinic-specific table when supplied.
- Otoacoustic emissions and screening audiometry are not diagnostic audiograms. Auditory brainstem response estimates hearing when behavioral testing is unreliable.
- Aural rehabilitation includes hearing aid fitting, cochlear implant candidacy, assistive technology, communication repair, and family training.
Worked example
An audiogram shows right air-conduction thresholds at 50 dB HL across speech frequencies and right bone-conduction thresholds at 10 dB HL; left thresholds are normal. The right ear has a moderate conductive hearing loss because bone conduction is normal and the air-bone gap exceeds 10 dB. The next step is otologic evaluation and masking as needed to confirm the true bone thresholds.
Traps
Do not interpret unmasked bone thresholds as true ear-specific hearing. Do not call a failed screening a diagnosis. Do not ignore speech-in-noise complaints when pure-tone thresholds look mild. Do not assume every hearing loss is helped equally by amplification.