Hearing Aid fitting and developmental outcomes of children fit according to either the NAL or DSL prescription : fit-to-target, audibility, speech and language abilities
Date
2017Author
Ching, Teresa
Zhang, Vicky
Johnson, Earl
Van Buynder, Patricia
Hou, Sanna
Burns, Lauren
Button, Laura
Flynn, Christopher
McGhie, Karen
Metadata
Show full item recordAbstract
Objective: This study compared hearing aid (HA) fitting outcomes and developmental
outcomes of children with hearing loss at 5 years of age.
Design and study sample: HA settings of 232 children that were fit according to either the
NAL or the DSL prescription were analysed as part of a longitudinal study on outcomes of
children with hearing impairment (LOCHI). A randomised trial of prescription was
implemented for a subset of 163 children for comparison of fitting and developmental
outcomes.
Results: Deviation from targets and root-mean-square (rms) error in HA fitting revealed no
significant difference between fitting prescriptions. Aided audibility as quantified by using
the Speech Intelligibility Index (SII) model showed that DSL provided higher audibility than
NAL at low and medium input levels but not at high input levels. When hearing loss
desensitization was incorporated in the calculation of SII, the randomised trial of prescription
revealed differences in audibility between prescription groups only at low input levels, but
not at medium or high input levels. There were no significant group differences in speech
production, perception, language and functional outcomes.
Conclusions: Proximity to prescriptive targets were similar between fitting prescriptions.
Although aided audibility varied between groups, developmental outcomes were similar.