Gainesville, Fla — In a University of Florida (UF) study of 56 college students who believed they had normal hearing, 25% did not have normal hearing sensitivity.

The unexpected discovery was made during the early stages of another UF study. Researchers at the College of Public Health and Health Professions were recruiting college students with normal hearing for a study on temporary hearing loss and personal music players.

The resulting findings were derived from 56 college students with an average age of 21 years old. Prospective participants who reported normal hearing in initial phone interviews were asked to visit the lab for hearing tests to determine their study eligibility. The participants completed a health survey and a questionnaire about their previous exposure to loud noise, such as playing a musical instrument, listening to personal music players, using lawn equipment, or attending sporting events or concerts. Participants then received hearing tests in a sound booth at all of the sound frequencies used in a traditional full clinical hearing test.

In 25% of the participants, researchers measured 15 decibels or more of hearing loss at one or more test frequencies, an amount that is not severe enough to require a hearing aid, but could disrupt learning.

Of the participants who demonstrated hearing loss, 7% had 25 decibels or more of hearing loss, which is clinically diagnosed as mild. The loss occurred in both the range of frequencies identified as “speech frequencies” because of their importance for speech discrimination, as well as the higher frequencies of 6 and 8 kilohertz.

Lead researcher Colleen Le Prell, an associate professor in the department of speech, language and hearing sciences, said in the press statement, “Several experts have speculated that increased rates of hearing loss in young adults may be related to the popularity of personal music players. The UF study did find that the highest levels of high frequency hearing loss were in male students who reported using personal music players.”

More research is needed with a larger sample size to determine the role of personal music players and gender in noise-induced hearing loss, Le Prell added.

Le Prell is now calling for more thorough hearing tests in schoolchildren and better hearing health education for children and adolescents.

She said, “When you look carefully at hearing loss at specific frequencies or higher frequencies than you would in a traditional school-based hearing test, you find a much, much higher rate of hearing screening failures. The implication is that the current screening protocols are potentially missing a lot of hearing loss, based on the kinds of failure rates that we’ve detected when you broaden the criteria.”

The study findings appeared in a special supplement of the March issue of the International Journal of Audiology.

SOUCE: The University of Florida