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Understanding Adult Literacy in the U. S.

Research indicates that there continues to be a need for Federal investment in adult education programs, in part because of data suggesting that the United States is losing ground to many of its economic competitors as measured by the employment-related skills of working-age adults. The Program for the International Assessment of Adult Competencies (PIAAC) is a cyclical, large-scale study that was developed under the auspices of the Organization for Economic Cooperation and Development (OECD). PIAAC is a direct household assessment designed to assess and compare the basic skills and competencies of adults around the world. The assessment focuses on cognitive and workplace skills needed for successful participation in 21st-century society and the global economy.  Learn more about the 53 million U. S. adults with low literacy skills and the 74 million adults with low numeracy skills here.

The PIAAC Gateway provides access to U.S. and international resources on PIAAC. The Gateway includes information and resources for researchers, practitioners, program managers, policy makers, and more. The PIAAC Gateway includes the interactive U. S. Skills Map which shows literacy and numeracy rates for each state and county.

Recent Research

The What Works Clearinghouse (WWC) reviewed the research on Washington State’s Integrated Basic Education Skills and Training (I-BEST) program and its impacts on community college students. Based on the research, the WWC found that I-BEST has positive effects on industry-recognized credential, certificate, or license completion; potentially positive effects on short-term employment; potentially positive effects on short-term earnings; and no discernible effects on credit accumulation. Read the full report and learn more about the studies that contributed to this rating.

In order to help understand and improve the ability of the adult education system to provide services, researchers funded by the Institute of Education Sciences have been conducting various research projects in partnership with adult education providers. Four such studies include:

  • For example, Career Pathways Programming for Lower-Skilled Adults and Immigrants conducted mixed-methods research in partnership with Chicago, Houston, and Miami. This work helped each city understand what types of career pathways adult education programs were offering and who was participating in such programing. This type of information helps programs, cities, and the system more broadly understand and adjust to the needs of learners and communities.
  • The New York State Literacy Zone Researcher-Practitioner Partnership focused on improving the ability of case managers to help adult learners leverage wrap-around services and access and succeed in adult education and training programs. This project helped develop tools and training for case managers and conduct an exploratory pilot study of these tools to see if they predicted learner outcomes, such as persistence in a program.
  • Nearly 43 million U.S. adults lack the basic English literacy skills required to succeed in the workforce and achieve economic self-sufficiency. The Workforce Innovation and Opportunity Act (WIOA) is the key federal investment helping adults acquire these and other important skills, as well as to earn a high school equivalency credential. WIOA encourages adult education programs to use evidence-based strategies to improve services and participant success. This systematic research review, Adult Education Strategies: Identifying and Building Evidence of Effectiveness, suggests a need for more rigorous studies, as there is not yet much evidence to guide decision making around instructional and support strategies for adult learners. The appendices for the Adult Education Strategies: Identifying and Building Evidence of Effectiveness snapshot may be found here: https://ies.ed.gov/ncee/pubs/2021007/pdf/2021007a.pdf.
  • Developed by the What Works Clearinghouse™ (WWC) in conjunction with an expert panel, this guide draws upon studies of interventions that include one or more of the career pathways components defined under the WIOA. It focuses on promising interventions where there is evidence of improved educational or labor market outcomes. This guide, Designing and Delivering Career Pathways at Community Colleges, provides community colleges with five specific recommendations for supporting occupational skills training through career pathways.

In 2012, the Institute of Education Sciences funded the Center for the Study of Adult Literacy (CSAL), which developed a curriculum and technology for adults reading between the 3rd- and 8th-grade levels. In 2020, IES funded additional development research to help refine an interactive, online reading comprehension program, AutoTutor for Adult Reading Comprehension (AT-ARC). This blog summarizes an IES-funded study conducted by CSAL that identified four possible subgroup categories of adult struggling readers based on their performance on lower-level competencies (phonological awareness, decoding, vocabulary) and higher-level competencies (comprehension, inferencing, background knowledge).

Emerging Research

The Office of Career, Technical, and Adult Education (OCTAE) at the U. S. Department of Education uses national leadership funds from section 242 of AEFLA to conduct rigorous research and evaluation. OCTAE is currently collaborating with the Institute of Education Sciences to conduct two new studies.  The first study, a study of WIOA implementation during program year 2019 -2020 is designed to provide implementation information on AEFLA programs, with a focus on how the changes contained in WIOA appear to be shaping the services provided by adult education programs and the populations such programs serve. A feasibility study will summarize what is known about effective adult education activities and services, identify policy-relevant activities or services that are feasible and appropriate to evaluate rigorously, and present design options for evaluating those activities or services.

Additionally, the Institute of Education Sciences is also currently funding, the Georgia Partnership for Adult Education and Research (GPAER) a collaboration among researchers at Georgia State University and leadership at the Georgia Office of Adult Education: Technical College System of Georgia to help understand adult literacy programs across the state. This ongoing work is conducting mixed-methods studies to understand program features, learner characteristics, and indicators of beneficial learner outcomes.


Finally, the LINCS Resource Collection provides online access to freely-available high-quality, evidence-based, vetted materials to help adult education practitioners and state and local staff improve programs, services, instruction, and teacher quality. Spanning 16 topic areas, the collection includes research articles and briefs.