Mild hearing loss is a misnomer. I do not know what word to substitute but mild hearing losses are not a mild problem. The data is clear. Children with mild hearing loss are at risk for academic, speech-language, and social-emotional difficulties. Newborn hearing screening does not always pick up mild hearing loss so babies with mild hearing loss may not get identified until they demonstrate delays.
Why is newborn hearing screening missing mild hearing loss?
Current standard newborn hearing screening techniques are good at identifying moderate or greater hearing loss. So when the baby passes hearing screening the family is told the baby has normal hearing. Since the parents and pediatricians have been told that the baby has normal hearing, if concerns develop, it may not occur to parents or the pediatrician that hearing loss may be a factor.
What exactly is mild hearing loss?
The definition of mild hearing loss varies depending on the researcher so results indicating the effects of mild hearing loss vary. Some audiologists define mild hearing loss as hearing thresholds of 15-30 dB, others use 20-40 dB. Statistics vary from 1-3% of the newborn population to 54/1000 in the school population. What ever criteria is used results in a significant number of affected children. The topic cannot be ignored.
What are the effects of a mild hearing loss?
Mild hearing loss is an invisible acoustic filter. The speech signal is not sufficiently loud and clear. Children with mild hearing loss will have less access to speech. A child with a 30 dB hearing loss will miss 25-40% of what happens in the classroom. A child with a 35-40 dB hearing loss will miss about 50% of what happens in the classroom. Bess et al, (1998) reported that 37% of children with minimal hearing loss (mild or unilateral) failed a grade by third grade.
A child with mild hearing loss will hear speech that is spoken close to the child, but when the child is 10 feet from the person talking, it will be difficult to hear. This is not an insignificant problem. More than 80% of what children learn they learn by overhearing things not specifically directed to them (incidental learning). If a child has, even a mild hearing loss, he will miss a lot of what is said, resulting in delayed language. Likely the delay will not be recognized for several years by which time we are talking about having to try and correct deficits rather then preventing delays.
Children with a mild hearing loss can be expected to have more problems hearing in noise then their typically hearing peers. Since the world is a noisy place it is not possible to avoid noise. If speech perception decreases in noise we expect a child to have language learning, and academic delays.
Middle ear disease?
Children with mild hearing loss can have a more significant problem from middle ear disease than children with normal hearing. Middle ear disease can decrease hearing by as much as 15-30 dB. If you have normal hearing, having a drop of 20 dB may not be a problem but if you have a hearing loss of 30 dB, an additional 20 dB drop can be devastating. Parents and physicians need to be vigilant and move quickly if a child has a mild hearing loss.
Do children with mild hearing loss need hearing aids?
Audiologists do not agree on the answer to this question. I am in the group that believes we need to do whatever we can do to assure that children hear everything around them. I will do extensive testing to see how a child is hearing, including speech perception as soon as a child can do that task. If a child is having trouble hearing soft speech that is a concern, and for me, that usually means hearing aids will be beneficial. For school, children with mild or unilateral hearing losses need FM systems to reduce the negative effects of distance and background noise.
Counseling about mild hearing loss.
The worse thing we can say to a family is “it’s only mild.” It is not a mild problem. The data is very clear that children with mild hearing losses struggle. Does this mean they will never succeed? No, of course not. But it does mean that they will have to work harder. So let’s do what we can to make things as easy as we can. Let’s use technology and provide necessary therapy and school assistance. Our goal is to have all kids with any degree of hearing loss be able to do whatever they want to do.