Instrument Fitting Flashcards

Which real-ear measurement (REM) target is most commonly used when fitting hearing aids to adults using evidence-based best practices?

Answer: NAL-NL2

NAL-NL2 (National Acoustic Laboratories Non-Linear version 2) is a widely adopted prescriptive target for fitting hearing aids in adults.

When performing a real-ear aided response (REAR) measurement, the probe microphone is placed:

Answer: Approximately 5–6 mm from the eardrum

The probe tube is inserted to approximately 5–6 mm from the tympanic membrane to accurately capture the sound at the eardrum.

A patient reports that soft speech sounds are inaudible even at maximum volume. The MOST likely fitting issue is:

Answer: Insufficient gain for soft inputs

Insufficient gain for soft-level inputs means quiet sounds are not amplified enough to reach audibility.

The DSL m[i/o] prescriptive method was specifically developed for:

Answer: Pediatric populations and infants

DSL m[i/o] (Desired Sensation Level) was designed to optimize audibility of speech for children, including infants.

Which term describes the maximum output of a hearing aid regardless of input level?

Answer: OSPL90

OSPL90 (Output Sound Pressure Level at 90 dB input) is the standardized measure of a hearing aid's maximum output.

A first-time hearing aid user complains that their own voice sounds hollow or like they are talking in a barrel. This is most likely caused by:

Answer: The occlusion effect

The occlusion effect occurs when a closed earmold blocks the ear canal, amplifying bone-conducted low-frequency energy of one's own voice.

To reduce the occlusion effect without sacrificing low-frequency amplification for a patient with a sloping high-frequency loss, the best earmold modification is:

Answer: Increase vent diameter

Increasing the vent diameter allows low-frequency bone-conducted sound to escape, reducing the hollow sensation without affecting amplification for patients who do not need low-frequency gain.