title: A cross-over, double-blind comparison of the NAL-NL1 and the DSL v4.1 prescriptions for children with mild to moderately severe hearing loss.
abstract: The relative effectiveness of the NAL-NL1 and the DSL4.1 prescriptions for 48 children with mild to moderately severe hearing loss was studied using a double-blind, four-period, two-treatment cross-over design in Australia and in Canada. Evaluations included speech perception tests, loudness ratings, reports from parents and teachers on functional performance in real life, children's self-reports, paired-comparison judgements of intelligibility, and children's preferences in real-world environments. Electroacoustic measures of hearing aids revealed that gain differences dominated the comparison. Across trials and measures, individual Australian children consistently preferred either the NAL-NL1 or the DSL v.4.1 prescription. An overall figure of merit (FOM), calculated by averaging the standardized difference scores between prescriptions for all measures, revealed that the strongest prescription-related differences were found in Australia. On average, an advantage and preference for the NAL-NL1 prescription was associated with lesser degrees of hearing loss. This research provides evidence on the effectiveness of the NAL-NL1 and DSL v.4.1 prescriptions, and highlights the need for evaluating and fine-tuning amplification to meet the diverse needs of individual children in real life.
authors.affiliation: National Acoustic Laboratories, Australian Hearing, Chatswood, Australia. Teresa.Ching@nal.gov.au
authors.forename: Teresa Y C
authors.initials: TY
authors.lastname: Ching
authors.forename: Susan D
authors.initials: SD
authors.lastname: Scollie
authors.forename: Harvey
authors.initials: H
authors.lastname: Dillon
authors.forename: Richard
authors.initials: R
authors.lastname: Seewald
mesh_terms: D000293:Adolescent; D001309:Auditory Threshold; D001315:Australia; D002170:Canada; D002648:Child; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006310:Hearing Aids / Q000592:standards; D034381:Hearing Loss / Q000503:physiopathology* / Q000523:psychology / Q000534:rehabilitation*; D006801:Humans; D007600:Judgment; D008144:Loudness Perception; D008297:Male; D057240:Patient Preference; D055656:Prescriptions / Q000592:standards; D017755:Prosthesis Fitting; D012720:Severity of Illness Index; D013065:Speech Intelligibility; D013067:Speech Perception; D016896:Treatment Outcome; D055815:Young Adult