EVALUATION OF SUBJECTIVE AND FUNCTIONAL OUTCOME MEASURES IN HEARING REHABILITATION IN THE DISPENSER'S PRACTICE

Kaandorp MW (1), Goverts ST (1), Drok T (2), Kramer SE (1), Festen JM (1).

(1) ENT-Audiology, VU University Medical Center, Amsterdam, The Netherlands; (2) Hinkgroep, Amersfoort, the Netherlands.

Next to functional outcomes, subjective outcome measures are considered increasingly important in hearing rehabilitation. Most research in this domain includes patients of audiological centers, whereas in The Netherlands an increasing proportion of hearing aid applicants is seen by a dispenser only. Aiming to ensure adequate quality of audiological care, we investigated self reported and functional outcome measures. We included 237 hearing-aid users, clients of six hearing-aid dispensers. Mean age was 67 years (27 – 87 y), mean pure-tone hearing loss (averaged across 1 – 4 kHz) was 50 dB (24 - 85 dB). Main outcome measures were the International Outcome Inventory for Hearing Aids (IOI-HA) that measures two aspects of hearing aid use (improvement and residual participation limitation) and a functional test, measuring spatial speech perception in noise (SRT). Other parameters taken into account were degree of hearing loss, years of hearing aid experience, age and five factors of subjective auditory functioning (Amsterdam Inventory on Auditory Disability and Handicap; AIADH). Hearing aids were divided into four categories, based on hardware price.

Regression analysis showed that both IOI factors are determined by self-rated auditory performance (AIADH), especially the ability to understand speech in noise. For improvement a small positive effect of degree of hearing loss was found. Other parameters including SRT showed minor or no relation. Regression analysis showed that SRT scores are determined by age and hearing loss.

In a dispenser’s population, the IOI factors improvement and residual participation limitation are mostly determined by subjective evaluation of auditory function. Age and type of hearing aid do not play a role. Functional outcomes do not seem to play a major role in self rated outcome measures. Implications of these findings for hearing rehabilitation practice will be discussed.

E-mail: mw.kaandorp@vumc.nl