(Photo credit: Murdoch Children's Research Institute)
A unique databank that profiles children with hearing loss will help researchers globally understand why some children adapt and thrive, while others struggle. The Victorian Childhood Hearing Impairment Longitudinal Databank, which has collected information for eight years, is featured in the latest International Journal of Epidemiology.
Its data shows that language development and speech in hearing-impaired children lags behind other children, despite advancements in earlier detection and intervention in the past decade. The paper's* lead author, Murdoch Children's Research Institute's (MCRI) Dr Valerie Sung, says researchers world-wide can use the databank to answer questions around childhood hearing loss.
"This register can help us understand why some children with a hearing loss do so well, while others experience greater difficulties," she says.
"Universal newborn hearing screening is detecting hearing loss earlier than ever before, usually within a few weeks of birth.
"Children with hearing loss have very early access to hearing aids, early intervention services and for some, cochlear implantation. It was expected that hearing-impaired children would quickly come to enjoy the same language and educational outcomes as their hearing peers.
"However, early clinical diagnosis and intervention does not guarantee equality in health outcomes, with language and related outcomes of children with hearing loss remaining on average well below population means and the children's true cognitive potential.
"Demonstrating the reasons for this inequality has been hampered until now by the lack of population based prospective research."
The Victorian Childhood Hearing Impairment Longitudinal Databank (VicCHILD) is a population-based longitudinal databank open to every child with permanent hearing loss in Victoria.
VicCHILD started in 2012 and stems from 25 years of work by The Royal Children's Hospital and MCRI. At the end 2018, 807 children were enrolled and provided baseline data. By 2020 more than 1000 children will be taking part, making it the largest hearing databank in the world.
VicCHILD collects data at enrolment, two years of age, school entry and late primary /early high school. It involves parent questionnaires, child assessments and taking saliva samples.
Dr Sung, who is also a honorary fellow at the University of Melbourne, says about 600 Australian infants each year are diagnosed with congenital hearing loss within weeks of birth.
"As these children grow, they can face challenges in things that come naturally to others like language and learning. This can impact their quality of life," she says.
"Hearing loss incurs significant burden and medical costs and impacts adversely on educational attainment and employment opportunities.
"This important bank of information could improve interventions and ultimately the lives of children with hearing loss and their families. It will also act as a platform for research trials to understand the effectiveness of different interventions."
Researchers from The Royal Children's Hospital and the University of Melbourne also contributed to the databank.
*Publication: Valerie Sung, Libby Smith, Zeffie Poulakis, Rachel Burt, Peter Carew, Sherryn Tobin and Melissa Wake. 'Data Resource Profile: Victorian Childhood Hearing Impairment Longitudinal Databank (VicCHILD)'. International Journal of Epidemiology.
The study was supported by The Royal Children's Hospital Foundation [2014-430]; The Murdoch Children's Research Institute; the Phyllis Connor Memorial Trust; the Deafness Foundation; the National Health and Medical Research Council (NHMRC) Centre of Research Excellence Grant ; the Kyle Patrick Lamsam Convery Foundation; the Nelson Alexander Charitable Foundation and a Royal Australasian College of Physicians Cottrell Research Establishment Fellowship. Ongoing support from The Royal Children's Hospital Foundation [2018-999] is available until 2022. VS was supported by Australian National Health and Medical Research Council (NHMRC) Early Career Fellowship  and a Melbourne Children's Clinician Scientist Fellowship. MW was supported by NHMRC Senior Research Fellowship 1046518 and by Cure Kids New Zealand. PC was supported by NHMRC Centre of Research Excellence in Child Language 1023493. RAB was supported by the HEARing CRC, established and supported under the Cooperative Research Centres Program - An Australian Government Initiative. Research at the Murdoch Children's Research Institute is supported by the Victorian Government's Operational Infrastructure Support Program. The researchers were independent of the funders.