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Peggy G. Carr, Ph.D.
Acting Commissioner of the National Center for Education Statistics

NCES Statement on PIAAC 2014 Prison Study
November 15, 2016

Commissioner Peggy G. Carr's Briefing Slides MS PowerPoint (4.83 MB)

Today, the National Center for Education Statistics is releasing (NCES) "Highlights from the U.S. PIAAC Survey of Incarcerated Adults: Their Skills, Work Experience, Education, and Training."

The Program for the International Assessment of Adult Competencies (PIAAC) is an international large-scale assessment developed by the Organization for Economic Cooperation and Development (the OECD). The U.S. PIAAC Survey of Incarcerated Adults follows two earlier studies, conducted by NCES in the 1990s and early 2000s, which assessed the skills of incarcerated adults in the United States.

This is the first time in more than a decade that an assessment of literacy skills of imprisoned adults in the United States has been conducted. Furthermore, this the first such large-scale assessment of numeracy skills among U.S. prisoners. The current sur­vey is an extension of this earlier work and continues the ongoing analysis and conversation about the skills and experiences of the U.S. prison population.

The report—Highlights from the U.S. PIAAC Survey of Incarcerated Adults: Their Skills, Work Experience, Education, and Training: Program for the International Assessment of Adult Competencies: 2014—is designed to provide policymakers, administrators, educators, and researchers with information to improve educational and training opportunities for incarcerated adults and foster skills they need to return to, and work successfully in, society upon release from prison.

Overall, the U.S. incarcerated population had lower average literacy and numeracy scores than the general U.S. household population.

Other key findings include the following:

About the PIAAC Prison Study

The PIAAC Prison Study is a nationally representative survey of the skills of incarcerated adults in U.S. state and federal prisons. The prison study was administered to a nationally representative sample of more than 1,300 adults between the ages of 18 and 74 in 98 prisons. While the PIAAC target population was 16- to 74-year-olds, the prison sample did not include 16- or 17-year-olds.

The assessment was administered from February through June of 2014. The prison study is part of the PIAAC household study, a large-scale, international assessment conducted in the United States and 33 other countries in 2012 and 2014. In the United States., the combined results of 2012 and 2014 household data collection were released earlier in 2016.  The combined U.S. household data are used for comparison with the prison study results. This study is a continuation of two previous U.S. prison studies: The National Adult Literacy Survey (NALS), conducted by the NCES in 1992, and the National Assessment of Adult Literacy (NAAL), conducted by NCES in 2003.

How the PIAAC U.S. Prison Study was conducted

The PIAAC respondents were interviewed to complete a background questionnaire before administering the direct assessments. Bilingual interviewers conducted the prison-specific background questionnaire on a laptop computer.

Total assessment time lasted for approximately two hours – with the background questionnaire taking about 45 minutes, and respondents taking roughly 60 minutes completing the assessment. The background questionnaire focused on inmates' participation in prison specific programs and activities, academic programs and ESL classes, as well as experiences with prison jobs and involvement in vocational training and nonacademic programs, such as employment readiness classes.

After completing the questionnaire, inmates who were familiar with computers and were willing to take a computer-based version of the assessment took the direct assessment on laptop computers. The remaining inmates took the paper-and-pencil version of the assessment. The majority of inmates took the assessment on a laptop.

The same assessment used in the PIACC household study was used in the Prison Study. Participants were assessed on literacy and numeracy.

Literacy was defined by the PIAAC framework as "understanding, evaluating, using and engaging with written text to participate in society, to achieve one's goals and to develop one's knowledge and potential."

Numeracy in the PIAAC framework was defined as "the ability to access, use, interpret, and communicate mathematical information and ideas, to engage in and manage mathematical demands of a range of situations in adult life."

Who took the Prison Study

An estimated 1.6 million adults were incarcerated in U.S. prisons in 2013. The prison population is younger, with more than 70 percent of inmates under the age of 45, while the household population is more evenly distributed across age groups.

The demographic characteristics of U.S. incarcerated adults are significantly different in many respects from those of the general population of adults in U.S. households. Compared to the household population, a large proportion of prison inmates are male (93 percent), compared to 49 percent in households. While White adults make up about two-thirds of the overall U.S. population, they account for only one-third (34 percent) of the state and federal prison population. Black and Hispanic adults are both disproportionately overrepresented in the prison population, together accounting for almost 60 percent of U.S. inmates.

While nearly 40 percent of household adults have some type of college degree, only six percent of U.S. prisoners have some college education, with most of those at the associate's degree level. For most U.S. incarcerated adults, a high school credential was the highest level of educational attainment (64 percent), and the highest level of education for 30 percent of inmates was below a high school degree.

Performance in Literacy for Incarcerated Adults 18-74

The U.S. average score in literacy in prison (249) was lower compared to household populations (270). Compared to the household population score of Blacks (240), the average literacy scores of incarcerated Black adults (245) were not measurably different. The same is true when comparing the Hispanic household populations (235) with incarcerated Hispanic adults (239). But white prisoners had significantly lower scores (265) than the white household population (282).

Performance in Numeracy for Incarcerated Adults 18-74

In numeracy, across all races, the average scores of incarcerated adults of all races were lower than their peers in the household population.

Access to Prison Jobs

Incarcerated adults with a prison job had higher literacy scores than those without a prison job; however, average numeracy scores were not measurably different.

In general, these jobs were more likely to involve more use of some literacy skills than numeracy skills. Most inmates reported never using their literacy or numeracy skills in their current prison work.

Among incarcerated adults with a prison job, the three most commonly reported literacy tasks performed at least some of the time were reading directions or instructions (53 percent), reading letters or memos (50 percent), and reading manuals or reference materials (35 percent).

Education Completion in Prison

Altogether, 42 percent of incarcerated adults had completed some level of education during their current incarceration. Almost three in five incarcerated adults (58 percent) completed no further formal education beyond the level they had on entering to prison, and about one in five (21 percent) obtained a high school credential during their current period of incarceration.

About one-third of the 64 percent of incarcerated adults had attained a high school credential. Twenty-one percent of incarcerated adults were currently studying for a formal degree or credential. While 70 percent reported wanting to enroll in an academic class or program, of those, 25 percent were on a waiting list for an academic class or program. Thirty percent reported not wanting to enroll in an academic class or program.

Job Training Participation

Less than half of incarcerated adults participated and completed job training – with 42 percent of incarcerated adults having completed some level of education during their current prison term and 21 percent of incarcerated adults were currently studying for a formal degree or credential.

However, 70 percent of incarcerated adults wanted to enroll in an academic class or program; 25 percent of those who wanted to enroll were on a wait list to enroll. 23 percent of incarcerated adults participated in job training programs and 14 percent were on a waiting list for a job training program.

For More Information

This statement highlights some of the major findings from U.S. 2014 U.S. Program for the International Assessment for Adult Competencies (or PIAAC) Prison Study. For more information on PIAAC and the 2012/2014 U.S. results, please visit the PIAAC website at

Commissioner Peggy G. Carr's Briefing Slides MS PowerPoint (4.83 MB)