Hearing aid verification while using the manufacturers targets
Hearing aid verification is mostly done based on NAL-NL1, NAL-NL2 or DSL 5.0. These are scientifically determined targets for hearing aids.
Hearing aid manufacturers also have their own view on the sound level that a hearing impaired should receive from the hearing aids. Therefore, these hearing aid manufacturers developed their own calculations. The hearing aid specialist should choose one of these verification rules. Examples of these rules are: Phonak Target Match, Oticon AutoFit, Signia AutoFit, Unitron TrueFit, Starkey Auto Path, Resound SmartFit AutoREM.
Every hearing aid manufacturer included its own view in regards to the level of amplification for intelligibility and comfort in numerous circumstances in these calculations, which are based on the aforementioned scientific calculations.