Probe Microphone Measurement
Also written as: PMM — Probe Microphone Measurement
A clinical procedure in which a thin probe tube placed in the ear canal measures the sound pressure level at the eardrum, used to verify hearing aid output against prescribed targets.
Full Definition
Probe microphone measurement (PMM), also called real-ear measurement (REM), involves inserting a fine silicone tube alongside the hearing aid in the ear canal to capture sound pressure levels close to the tympanic membrane. The technique enables clinicians to compare amplified output directly against prescriptive fitting targets (such as NAL-NL2 or DSL) without relying solely on simulated coupler data. Editors will encounter this term in clinical protocols, fitting verification reports, and evidence-based practice guidelines. Although 'probe microphone measurement' and 'real ear measurement' are often used interchangeably, the former emphasises the measurement tool and the latter the measurement site.
Usage
Usage note: Distinguish from 'real ear measurement (REM)': in most UK and Australian clinical literature, these terms are interchangeable, but some manufacturers use 'probe microphone measurement' more broadly to include non-ear measurements. Clarify with the client if editing regulatory submissions.
In Context
- "Probe microphone measurement confirmed that the aided output matched the NAL-NL2 target to within 3 dB across all test frequencies." — Hearing Aid Verification Report
- "The clinical guideline mandated probe microphone measurement as the preferred method of hearing aid verification for all new fittings." — National Clinical Protocol