Incidence refers to the number of new cases of a disorder identified within a specified time period. Because there is not a national registry in the United States tracking newly identified patients with tinnitus, published incidence rates stem from population-based community studies. Most notably, a 10-year prospective study performed in Beaver Dam, Wisconsin, followed 2,922 participants who self-identified as having no tinnitus at the start of data collection. The 10-year cumulative incidence of tinnitus in the study population was 12.7%. Significant associations were found with arthritis, head injury, smoking, and, among women only, hearing loss. Alcohol consumption was associated with a decreased risk, along with age for women and obesity for men (Nondahl et al., 2010).
Prevalence refers to the number of individuals with a disorder in a specified time period. The prevalence of tinnitus is estimated by the National Center for Health Statistics (a division of the Centers for Disease Control [CDC]) from data collected in the National Health and Nutrition Examination Survey (NHANES). Since 1999, the NHANES includes questions about ringing, roaring, or buzzing in the respondent's ears or head. In 2005, the tinnitus question was refined to adult participants (ages 20–69 years) reporting that they were "bothered by ringing, roaring or buzzing" that lasts for more than 5 minutes. The prevalence has ranged from 7.1% (2007–2008; National Center for Health Statistics, 2016) to 14.6% (2011–2012; National Center for Health Statistics, 2016). This is consistent with findings in other countries, which reported a range of 10.2% to 15.1% in earlier studies (Møller, 2011).
It is notable that in the 2011–2012 NHANES findings, 9.3 % of those reporting bothersome tinnitus reported it as a big or a very big problem, and 39.3% reported that they were bothered when going to sleep. Additionally, 81.5% indicated that they had the tinnitus for 3 months or longer, and 39.3% noted that they experience tinnitus almost always or at least once a day.
Review of the literature reveals inconsistent and broad ranges of prevalence for children with tinnitus, varying from 4.7% to 62.2%. This disparity is likely due to differences in describing the tinnitus, the question posed, response options, age, and study design (Rosing, Schmidt, & Baguley, 2016).