How do you compare literacy skills of adults from around the world?

Comparing literacy skills of adults around the world through PIAAC


Do adults have the literacy and problem-solving skills they need to successfully participate in 21st-century society? Are their skills improving, declining, or staying the same? How do skill levels compare among different countries?

The Program for the International Assessment of Adult Competencies (PIAAC) is a cyclical, large-scale study of adult skills and life experiences designed to answer these questions and focuses on education and employment. Nationally representative samples of adults between the ages of 16 and 65 are administered an assessment of literacy, numeracy, and problem-solving in technology-rich environments, as well as survey questions about their educational background, work history, the skills they use on the job and at home, their civic engagement, and sense of their health and well-being.


With our international colleagues at the Organisation for Economic Co-operation and Development (OECD) and the National Center for Education Statistics (NCES), Westat developed the PIAAC technical standards and guidelines and training materials for sampling, field operations, and more.
Westat field-tested and conducted the 2012 U.S. study in which more than 5,000 participants completed the interview and assessment.

The 2014 U.S. National Supplement was the second U.S. data collection in which more than 3,600 adults were surveyed from 3 key subgroups: unemployed adults, young adults (age 16 to 34), and older adults (age 66 to 74). In addition, about 1,300 adult inmates detained in federal and state prisons were interviewed and assessed.

The 2017 U.S. National Supplement was the third U.S. data collection that included a nationally representative sample of about 3,800 new adults (age 16 to 74). Westat is currently fielding PIAAC for the first round of Cycle II, along with 31 other countries.


The results of PIAAC are used to compare participating countries on the skills capacities of their workforce-aged adults and to learn more about relationships between educational background and employment and other outcomes.

Results from the 2014 U.S. National Supplement augmented the 2012 U.S. sample to permit more in-depth analyses of the cognitive and workplace skills of the U.S. population, in particular of the 3 key U.S. subgroups listed earlier.

The 2014 U.S. National Supplement also provided information on adults age 66 to 74 and incarcerated adults to make PIAAC data comparable with data collected by NCES in the 2003 National Assessment of Adult Literacy (NAAL) and make it possible to analyze change in adult skills over the decade between the 2 studies.

The 2017 U.S. National Supplement collected a nationally representative sample of the U.S. adult population for 16- to 74-year-olds and provides an additional sample. When combined with the 2012 and 2014 samples, these data will be used to produce indirect, state-level, and county-level estimates for the U.S.


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