McKay School of Education > News > Professor Presents Abroad on the Benefits of Cochlear Implants
Professor David McPherson Presents Abroad on the Benefits of Cochlear Implants
Despite the challenge of having to learn to hear in a new “electronic” way, children with hearing loss who receive a cochlear implant do better than those who use traditional hearing-assistance devices. The earlier the treatment, the better the outcome. These are among the conclusions of David McPherson’s review of literature on the subject. He and several colleagues presented their research in Warsaw in May.
McPherson and his colleagues reviewed research from many countries to test their hypothesis. “We have used studies, not only from the United States, but also from around the world,” McPherson said. “We are able to make a broad statement—one that carries weight abroad as well as at home.” They were examining data to see whether there is a relationship between age of intervention with a cochlear implant and language, literacy, and social skills. “The studies that we reviewed favor the hypothesis that the earlier the cochlear implant, the better the results,” McPherson affirmed.
A cochlear implant, sometimes known as “the bionic ear,” consists of electrodes inserted into the inner ear that stimulate the inner ear mechanism to produce hearing. This contrasts with hearing aids, which amplify sounds that are transmitted through the normal auditory system.
“We are stimulating the inner ear auditory nerve directly with the cochlear implant,” McPherson explained, “We call the type of hearing that is received from a cochlear implant ‘electric.’” Even though the hearing is different from regular hearing, it allows the user to differentiate sounds, such as picking speech out of ambient sound—a problem not well addressed with typical hearing aids.
McPherson and his colleagues employed a statistical technique called meta-analysis in dealing with the data they collected, which has never been done with this subject. Put simply, meta-analysis takes into consideration the statistical significance of each data set before computing its impact. In other words, not all data sets count equally—those that are less statistically powerful count less.
For instance, if researchers examined 40 different research reports on the effectiveness of cochlear implants versus typical hearing aids and found that 35 of the 40 showed no significant difference, yet the statistical significance of the remaining five was more powerful than the 35 combined, the conclusion would report that cochlear implants do in fact have a significant effect. If the 35 studies used small sample sizes and their statistics were not powerful, 5 studies may outweigh 35.
McPherson is an advocate for international collaboration. “One of the advantages of this kind of collaboration is that we can make an impact on a larger scale, rather than talk about the situation in the United States alone.”
The researchers intend to publish the findings presented in Warsaw.
1 June 2009