Age-adjusted prevalence of hearing impairment (HI) decreased across generations in the 20th century, suggesting that HI is partially preventable.

It is not known whether HI incidence differs by generation.

We examine whether HI incidence and change in pure-tone average (PTA) differ by generation and identify factors underlying these differences.

This cohort study used data from the Epidemiology of Hearing Loss Study (EHLS) and Beaver Dam Offspring Study (BOSS), a pair of studies of adults in Beaver Dam, Wisconsin.

Baseline examinations occurred from 1993 to 1995 in the EHLS and 2005 to 2008 in BOSS, with two 5-year follow-up examinations in each cohort.

This longitudinal cohort study assessed 3651 participants without HI at baseline who had follow-up data.