Objectives To address the question of whether, on a population level, early detection and amplification improve outcomes of children with hearing impairment. Design All families of children who were born between 2002 and 2007, and who presented for hearing services below 3 years of age at Australian Hearing pediatric centers in New South Wales, Victoria and Southern Queensland were invited to participate in a prospective study on outcomes. Children’s speech, language, functional and social outcomes were assessed at 3 years of age, using a battery of age-appropriate tests. Demographic information relating to the child, family, and educational intervention was solicited through the use of custom-designed questionnaires. Audiological data were collected from the national database of Australian Hearing and records held at educational intervention agencies for children. Regression analysis was used to investigate the effects of each of 15 predictor variables, including age of amplification, on outcomes. Results Four hundred and fifty-one children enrolled in the study, 56% of whom received their first hearing-aid fitting before 6 months of age. Based on clinical records, 44 children (10%) were diagnosed with auditory neuropathy spectrum disorder. There were 107 children (24%) reported to have additional disabilities. At 3 years of age, 317 children (70%) were hearing-aid users and 134 children (30%) used cochlear implants. Based on parent reports, about 71% used an aural/oral mode of communication, and about 79% used English as the spoken language at home. Children’s performance scores on standardized tests administered at 3 years of age were used in a factor analysis to derive a global development factor score. On average, the global score of hearing-impaired children was more than one standard deviation (SD) below the mean of normal-hearing children at the same age. Regression analysis revealed that five factors, including female gender, absence of additional disabilities, less severe hearing loss, higher maternal education; and for children with cochlear implants, earlier age of switch-on; were associated with better outcomes at the 5% significance level. Whereas the effect of age of hearing aid fitting on child outcomes was weak, a younger age at cochlear implant switch-on was significantly associated with better outcomes for children with cochlear implants at 3 years of age. Conclusions Fifty-six percent of the 451 children were fitted with hearing aids before 6 months of age. At 3 years of age, 134 children used cochlear implants and the remaining children used hearing aids. On average, outcomes were well below population norms. Significant predictors of child outcomes include: presence/absence of additional disabilities, severity of hearing loss, gender, maternal education; together with age of switch-on for children with cochlear implants.

Speech perception in children with hearing loss can be enhanced by improving their language abilities. Early age at cochlear implantation was also associated with better outcomes.

Hearing loss is an etiologically heterogeneous trait with differences in the age of onset, severity and site of lesion. It is caused by a combination of genetic and/or environmental factors. A longitudinal study to examine the efficacy of early intervention for improving child outcomes is ongoing in Australia. To determine the cause of hearing loss in these children we undertook molecular testing of perinatal “Guthrie” blood spots of children whose hearing loss was either detected via newborn hearing screening or detected later in infancy. We analyzed the GJB2 and SLC26A4 genes for the presence of mutations, screened for the mitochondrial DNA (mtDNA) A1555G mutation, and screened for congenital CMV infection in DNA isolated from dried newborn blood spots. Results were obtained from 364 children. We established etiology for 60% of children. One or two known GJB2 mutations were present in 82 children. Twenty-four children had one or two known SLC26A4 mutations. GJB2 or SLC26A4 changes with unknown consequences on hearing were found in 32 children. The A1555G mutation was found in one child, and CMV infection was detected in 28 children. Auditory neuropathy spectrum disorder was confirmed in 26 children whose DNA evaluations were negative. A secondary objective was to investigate the relationship between etiology and audiological outcomes over the first 3 years of life. Regression analysis was used to investigate the relationship between hearing levels and etiology. Data analysis does not support the existence of differential effects of etiology on degree of hearing loss or on progressiveness of hearing loss.

Objective To determine the influence of the presence of auditory neuropathy spectrum disorder (ANSD) on speech, language, and psycho-social development of children at three years of age. Design A population-based, longitudinal study was performed on outcomes of children with hearing impairment (LOCHI) in Australia. The demographic characteristics of the children were described, and their developmental outcomes were evaluated at three years of age. Performance of children with ANSD was compared with that of children without ANSD in the LOCHI study. Study sample There were 47 children with ANSD in the study sample. Results Sixty-four percent of children with ANSD have hearing sensitivity loss ranging from mild to severe degree, and the remaining have profound hearing loss. At three years, 27 children used hearing aids, 19 used cochlear implants, and one child did not use any hearing device. Thirty percent of children have disabilities in addition to hearing loss. On average, there were no significant differences in performance level between children with and without ANSD. Also, the variability of scores was not significantly different between the two groups. Conclusions There was no significant difference in performance levels or variability between children with and without ANSD, both for children who use hearing aids, and children who use cochlear implants.

Objectives This paper compares language development and speech perception of children with bimodal fitting (a cochlear implant in one ear and a hearing aid in the opposite ear) or bilateral cochlear implantation. Methods Participants were children enrolled in the Longitudinal Outcomes of Children with Hearing Impairment (LOCHI) study. Language development was assessed at 3 years of age using standardized tests. Speech perception was evaluated at 5 years of age. Speech was presented from a frontal loudspeaker, and babble noise was presented either from the front or from both sides. Results On average, there was no significant difference in language outcomes between 44 children with bimodal fitting and 49 children with bilateral cochlear implants; after controlling for a range of demographic variables. Earlier age at cochlear implant activation was associated with better outcomes. Speech perception in noise was not significantly different between children with bimodal fitting and those with bilateral cochlear implants. Compared to normal-hearing children, children with cochlear implants required a better signal-to-noise ratio to perform at the same level, but demonstrated spatial release from masking of a similar magnitude. Conclusions This study found that language scores for children with bilateral implants were higher than those with bimodal fitting or those with unilateral implants, but neither reached significance level.

Objective To determine the influence of choice of prescription and other child-, family- and intervention-related factors on speech, language, and functional performance of hearing-impaired children by three years of age. Design and study sample A randomized controlled design was implemented as part of a population-based, longitudinal study on outcomes of children with hearing impairment (LOCHI) in Australia. Two hundred and eighteen children were randomly assigned to either the NAL or the DSL prescription for first fitting of hearing aids. Their performance outcomes were evaluated. Results Prescriptive targets were closely matched in children's hearing aids. There were not significant differences in children's language, speech production, or functional performance between prescriptions. Parents' ratings of children's device usage and loudness discomfort were not significantly different between prescription groups. Functional performance within the first year of fitting together with degree of hearing loss, presence of additional disabilities, and maternal education explained 44% of variation in language ability of children by three years of age. Conclusions There was no significant association between choice of hearing-aid prescription and variance in children's outcomes at three years of age. In contrast, additional disability, maternal educational level, and early functional performance were significant predictive factors of children's outcomes.

Aetiology and age at implantation had significant effects on T-levels and C-levels.

OBJECTIVE To examine the impact of prescription on predicted speech intelligibility and loudness for children. DESIGN A between-group comparison of Speech Intelligibility Index (SII) and loudness, based on hearing aids fitted according to NAL-NL1, DSL v4.1, or DSL m[i/o] prescriptions. A within-group comparison of gains prescribed by DSL m[i/o] and NAL-NL2 for children in terms of SII and loudness. STUDY SAMPLE Participants were 200 children , who were randomly assigned to first hearing-aid fitting with either NAL-NL1, DSL v4.1, or DSL m[i/o]. Audiometric data and hearing aid data at 3 years of age were used. RESULTS On average, SII calculated on the basis of hearing-aid gains were higher for DSL than for NAL-NL1 at low input level, equivalent at medium input level, and higher for NAL-NL1 than DSL at high input level. Greater loudness was associated with DSL than with NAL-NL1, across a range of input levels. Comparing NAL-NL2 and DSL m[i/o] target gains revealed higher SII for the latter at low input level. SII was higher for NAL-NL2 than for DSL m[i/o] at medium- and high-input levels despite greater loudness for gains prescribed by DSL m[i/o] than by NAL-NL2. CONCLUSION The choice of prescription has minimal effects on speech intelligibility predictions but marked effects on loudness predictions.