The American Community Survey's six disability questions (ACS-6) aim to measure disability in accordance with the Americans with Disabilities Act of 1990 (ADA). However, the ACS-6 have not adapted to the ADA Amendments Act of 2008 (ADAAA), which expands the definition of major life activities to include major bodily functions. This article estimates the extent to which the ACS-6 undercount people with disabilities based on the expanded definition of major life activities. It also quantifies by how much disability prevalence estimated by the ACS-6 would increase if the ACS-6 were revised to align with the ADAAA.

This article explains how the work incapacity insurance system in the Netherlands measures an individual's ability to work. The authors then apply aspects of that method to estimate work capacity in a representative sample of U.S. working-age adults. By linking functional ability assessments based on the Dutch disability determination method with Dutch job profile data, the authors estimate individual work capacity and compare those estimates with U.S. Disability Insurance (DI) eligibility criteria. The analysis provides insight into the share of U.S. adults with earnings capacity below the DI program's substantial gainful activity threshold as well as variation by educational attainment.