It’s such an important question to answer. Problems with study methods are stopping international scientists from answering the question: What is children’s tinnitus hyperacusis prevalence internationally for ages 5 to 19? How common are T-H in children of different ages around the world? Tinnitus is hearing extra sounds or sound combinations-like ringing, buzzing, squealing-when there is no outside sound source. Hyperacusis is hearing sounds extra louder than other people so it hurts like a needle piercing the eardrum. Both are from hyperactive hearing systems.
Rosing et al. (2016) did a systematic review on prevalence of tinnitus and hyperacusis in children and adolescents aged 5 to 19. In evidence-based medicine, systematic reviews collect and analyze research papers and studies on a particular research question. Systematic reviews are supposed to give a complete summary of current scientific literature on that question, and are usually faster and cheaper than doing a whole new study. Rosing et al. found 131 original articles that met their review criteria published in English, German, Swedish, Norwegian and Danish peer reviewed scientific journals and two highly cited conference proceedings. Only 25 articles included ages 5 to 19, and had consistent enough methods to be included in Rosing et al’s systematic review. This is what they found:
Prevalence of tinnitus in children varied from 4.7% to 74.9%
Prevalence of hyperacusis in children varied from 3.2% to 17.1%
- Different age groups were studied, e.g. 5-12 years old, 5-18, 5-19, 9-16, 11-16, 13-15, 12-18, 13-19, 16-19.
- Different tinnitus definitions/questions used e.g. Have you ever heard noises in your ears? Have you heard noises in your ears during the past 6 months? Do you hear noises in your ears all the time?
- Different tinnitus answer options e.g. yes/no, ranking from no to very annoying, no/sometimes/often.
- Different hyperacusis definitions/questions used: e.g. Are you oversensitive to everyday low intensity sounds? Are you annoyed by normal everyday sounds? Are you oversensitive to noise?
- Different hyperacusis answer options e.g. yes/no, percentages of how annoyed e.g. 60%
- Few studies checked reliability of children’s answers e.g. did they understand the question?
- Age, gender and hearing status of the children make a difference but there were too many differences between studies to identify exactly how much.
Rosing et al. describe how the study data could not be pooled into larger sample sizes for stronger prevalence evidence. The tinnitus data could be the prevalence of tinnitus of any severity from brief temporary tinnitus to constant tinnitus. The wording of the tinnitus questions and tinnitus definitions greatly changed prevalence estimates and made it impossible to compare across studies. Different approaches to making sure children understood the question, and that answers were reliable, was also a problem.
The hyperacusis data had such different methods, articles reviewed couldn’t be compared at all.
The good news is that in 2015, the Pediatric Audiology Interest Group (PAIG) of the British Society of Audiology (BSA), with support from the British Tinnitus Association, developed Practice Guidance for working with children with tinnitus. This will help standardize measures so scientific studies on tinnitus prevalence are more consistent. That will help scientists directly compare prevalence studies more easily in future. Guidance for working with children with hyperacusis still needs to be developed.
Rosing et al. state: “There is an opportunity for researchers within the field of paediatric tinnitus and hyperacusis to find agreement on a standard way of assessing, defining and reporting prevalence and severity of tinnitus/hyperacusis. It would be valuable to obtain standardised information on prevalence, with well-defined questions and tight age ranges, or sampling at a specific age.”
Prevalence of distressing tinnitus and hyperacusis in children is so important. We need to know how many children around the world are affected. We need to make sure we have enough services to give proper care and treatment for all children troubled by tinnitus and hyperacusis around the world. This question is too important for scientists to waste time and effort on articles that don’t advance evidence-based science in this field of study.
The next time you see the media report prevalence of tinnitus or hyperacusis in children, stop and ask yourself. What age range of children? What tinnitus or hyperacusis prevalence question did the study ask? How did the study make sure the children understood the question and answered reliably? Did the researchers use an internationally agreed standard method of study for pediatric tinnitus and hyperacusis? And why didn’t the media publish the real story: it’s 2018 and we still don’t know how many children in the world have tinnitus or hyperacusis.
- Rosing, S. N., Schmidt, J. H., Wedderkopp, N., & Baguley, D. M. (2016, June 3), Prevalence of tinnitus and hyperacusis in children and adolescents: a systematic review. British Medical Journal Open. 6(6). Retrieved from https://bmjopen.bmj.com/content/6/6/e010596
- “What is EBM?”. Centre for Evidence Based Medicine. 2009-11-20. Archived from the original on 2011-04-06.
- Audiology BSo. Tinnitus in children: Practice guidance. 2015. Retrieved from https://www.thebsa.org.uk/
Photo Credit: Robert Collins at Unsplash
Jan L. Mayes MSc Aud(C) RAud is an international Eric Hoffer Award winning author, audiologist, and hearing healthcare educator. She specializes in tinnitus, hyperacusis, noise-induced hearing system damage, and darkly disturbing, macabre horror fiction.