Although data collection has improved in recent years, several aspects of general hearing loss in the United States continue to be problematic to quantify.
One tendency feeding this problem is the frequent lack of distinction between types, onsets, and severity levels of hearing loss; one often sees either "individuals with hearing loss" with a single line of percentages or totals, or, if one is lucky, one may see two lines: "severe" and "not severe."
Such is the state of deaf statistics within the federal government. Several private entities -- such as the Gallaudet Research Institute here at Gallaudet University and researchers at RIT/NTID -- have taken a stab at it, but are limited by the data available.
Speaking of RIT/NTID researchers, in 2012 they released a report that not only estimates an average prevalence of hearing loss within the U.S. of approximately 3.5%, but also work towards resolving other issues present in the data that include:
- Age distribution
- When searching for statistics by age, useful interpretation can be challenged by varying cutoff ages; for example, it is difficult to compare statistics from two different sources for school-age children when one source uses a range of 5-19 years of age, while another uses a range of 3-21.
- As mentioned above, definitions may vary – there may be no differentiation at all between levels of hearing loss, some differentiation, and arbitrary differentiations. For instance, surveys that examine statistics of "hearing," "hard of hearing," "moderately deaf," "severely deaf," and "profoundly deaf"; at what point does "hard of hearing" begin or end, in comparison to "hearing" or "moderately deaf"? Additionally, are technologies such as cochlear implants (which may render a profoundly-deaf individual into a hearing individual on an audiogram) accounted for?
All of the above-listed issues are perennial in spite of tremendous advancement in data collection, analysis, and interpretation; as such, they should always be kept in mind. One way to do this is to remember to ask yourself these questions:
- How was "deaf" defined in this survey?
- How are the figures expressed: as a numerical quantity (e.g., total number of deaf people), percentage (e.g., how much of the general (or disabled) population is deaf), or prevalence (e.g., there are x deaf people per 1,000)?
- Who is doing the counting?
- Is the source likely to want to skew the numbers? (For example, an organization of the deaf may want to represent the upper end of the range in order to appear to have more clout)
- How reliable is the source?
You may also use the yellow tabs above to navigate through the different sections of this guide. If you have any further questions, you can also use the box on the left to communicate with a librarian for more in-depth information.
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Reference and Instruction Librarian
Updated: September, 2012