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National Center for Education Statistics

Rescaled Data Files for Analyses of Trends in Adult Skills

In January 2022, NCES released the rescaled data files for three adult literacy assessments conducted several decades earlier: the 1992 National Adult Literacy Survey (NALS), the 1994 International Adult Literacy Survey (IALS), and the 2003 Adult Literacy and Lifeskills Survey (ALL). By connecting the rescaled data from these assessments with data from the current adult literacy assessment, the Program for the International Assessment of Adult Competencies (PIAAC), researchers can examine trends on adult skills in the United States going back to 1992. This blog post traces the history of each of these adult literacy assessments, describes the files and explains what “rescaling” means, and discusses how these files can be used in analyses in conjunction with the PIAAC files. The last section of the post offers several example analyses of the data.

A Brief History of International and National Adult Literacy Assessments Conducted in the United States

The rescaled data files highlighted in this blog post update and combine historical data from national and international adult literacy studies that have been conducted in the United States.

NALS was conducted in 1992 by NCES and assessed U.S. adults in households, as well as adults in prisons. IALS—developed by Statistics Canada and ETS in collaboration with 22 participating countries, including the United States—assessed adults in households and was administered in three waves between 1994 and 1998. ALL was administered in 11 countries, including the United States, and assessed adults in two waves between 2003 and 2008.

PIAAC seeks to ensure continuity with these previous surveys, but it also expands on their quality assurance standards, extends the definitions of literacy and numeracy, and provides more information about adults with low levels of literacy by assessing reading component skills. It also, for the first time, includes a problem-solving domain to emphasize the skills used in digital (originally called “technology-rich”) environments.

How Do the Released Data Files From the Earlier Studies of Adult Skills Relate to PIACC?

All three of the released restricted-use data files (for NALS, IALS, and ALL) relate to PIAAC, the latest adult skills assessment, in different ways.

The NALS data file contains literacy estimates and background characteristics of U.S. adults in households and in prisons in 1992. It is comparable to the PIAAC data files for 2012/14 and 2017 through rescaling of the assessment scores and matching of the background variables to those of PIAAC.

The IALS and ALL data files contain literacy (IALS and ALL) and numeracy (ALL) estimates and background characteristics of U.S. adults in 1994 (IALS) and 2003 (ALL). Similar to NALS, they are comparable to the PIAAC restricted-use data (2012/14) through rescaling of the literacy and numeracy assessment scores and matching of the background variables to those of PIAAC. These estimates are also comparable to the international estimates of skills of adults in several other countries, including in Canada, Hungary, Italy, Norway, the Netherlands, and New Zealand (see the recently released Data Point International Comparisons of Adult Literacy and Numeracy Skills Over Time). While the NCES datasets contain only the U.S. respondents, IALS and ALL are international studies, and the data from other participating countries can be requested from Statistics Canada (see the IALS Data Files/Publications and ALL Data pages for more detail). See the History of International and National Adult Literacy Assessments page for additional background on these studies. 

Table 1 provides an overview of the rescaled NALS, IALS, and ALL data files.


Table 1. Overview of the rescaled data files for the National Adult Literacy Survey (NALS), International Adult Literacy Survey (IALS), and Adult Literacy and Lifeskills Survey (ALL) 

Table showing overview of the rescaled data files for the National Adult Literacy Survey (NALS), International Adult Literacy Survey (IALS), and Adult Literacy and Lifeskills Survey


What Does “Rescaled” Mean?

“Rescaling” the literacy (NALS, IALS, ALL) and numeracy (ALL) domains from these three previous studies means that the domains were put on the same scale as the PIAAC domains through the derivation of updated estimates of proficiency created using the same statistical models used to create the PIAAC skills proficiencies. Rescaling was possible because PIAAC administered a sufficient number of the same test questions used in NALS, IALS, and ALL.1 These rescaled proficiency estimates allow for trend analysis of adult skills across the time points provided by each study.

What Can These Different Files Be Used For?

While mixing the national and international trend lines isn’t recommended, both sets of files have their own distinct advantages and purposes for analysis.

National files

The rescaled NALS 1992 files can be used for national trend analyses with the PIAAC national trend points in 2012/2014 and 2017. Some potential analytic uses of the NALS trend files are to

  • Provide a picture of the skills of adults only in the United States;
  • Examine the skills of adults in prison and compare their skills with those of adults in households over time, given that NALS and PIAAC include prison studies conducted in 1992 and 2014, respectively;
  • Conduct analyses on subgroups of the population (such as those ages 16–24 or those with less than a high school education) because the larger sample size of NALS allows for more detailed breakdowns along with the U.S. PIAAC sample;
  • Focus on the subgroup of older adults (ages 66–74), given that NALS sampled adults over the age of 65, similar to PIAAC, which sampled adult ages 16–74; and
  • Analyze U.S.-specific background questions (such as those on race/ethnicity or health-related practices).

International files

The rescaled IALS 1994 and ALL 2003 files can be used for international trend analyses among six countries with the U.S. PIAAC international trend point in 2012/2014: Canada, Hungary, Italy, Norway, the Netherlands, and New Zealand. Some potential analytic uses of the IALS and ALL trend files are to

  • Compare literacy proficiency results internationally and over time using the results from IALS, ALL, and PIAAC; and
  • Compare numeracy proficiency results internationally and over time using the results from ALL and PIAAC.

Example Analyses Using the U.S. Trend Data on Adult Literacy

Below are examples of a national trend analysis and an international trend analysis conducted using the rescaled NALS, IALS, and ALL data in conjunction with the PIAAC data.

National trend estimates

The literacy scores of U.S. adults increased from 269 in NALS 1992 to 272 in PIAAC 2012/2014. However, the PIAAC 2017 score of 270 was not significantly different from the 1992 or 2012/2014 scores.


Figure 1. Literacy scores of U.S. adults (ages 16–65) along national trend line: Selected years, 1992–2017

Line graph showing literacy scores of U.S. adults (ages 16–65) along national trend line for NALS 1992, PIAAC 2012/2014, and PIAAC 2017

* Significantly different (p < .05) from NALS 1992 estimate.
SOURCE: U.S. Department of Education, National Center for Education Statistics, National Adult Literacy Survey (NALS), NALS 1992; and Program for the International Assessment of Adult Competencies (PIAAC), PIAAC 2012–17.


International trend estimates

The literacy scores of U.S. adults decreased from 273 in IALS 1994 to 268 in ALL 2003 before increasing to 272 in PIAAC 2012/2014. However, the PIAAC 2012/2014 score was not significantly different from the IALS 1994 score.


Figure 2. Literacy scores of U.S. adults (ages 16–65) along international trend line: Selected years, 1994–2012/14

Line graph showing literacy scores of U.S. adults (ages 16–65) along international trend line for IALS 1994, ALL 2003, and PIAAC 2012/2014

* Significantly different (p < .05) from IALS 1994 estimate.
SOURCE: U.S. Department of Education, National Center for Education Statistics, Statistics Canada and Organization for Economic Cooperation and Development (OECD), International Adult Literacy Survey (IALS), 1994–98; Adult Literacy and Lifeskills Survey (ALL), 2003–08; and Program for the International Assessment of Adult Competencies (PIAAC), PIAAC 2012/14. See figure 1 in the International Comparisons of Adult Literacy and Numeracy Skills Over Time Data Point.


How to Access the Rescaled Data Files

More complex analyses can be conducted with the NALS, IALS, and ALL rescaled data files. These are restricted-use files and researchers must obtain a restricted-use license to access them. Further information about these files is available on the PIAAC Data Files page (see the “International Trend Data Files and Data Resources” and “National Trend Data Files and Data Resources” sections at the bottom of the page).

Additional resources:

By Emily Pawlowski, AIR, and Holly Xie, NCES


[1] In contrast, the 2003 National Assessment of Adult Literacy (NAAL), another assessment of adult literacy conducted in the United States, was not rescaled for trend analyses with PIAAC. For various reasons, including the lack of overlap between the NAAL and PIAAC literacy items, NAAL and PIAAC are thought to be the least comparable of the adult literacy assessments.

Education and Training Opportunities in America’s Prisons

By Dana Tofig, Communications Director, Institute of Education Sciences

The latest results from the Program for the International Assessment of Adult Competencies (PIAAC) reinforce some of what we know about the connection between education and incarceration—adults in prison, on average, have less formal education and lower literacy and numeracy skills than adults living in U.S. households.  But what about the education and training adults receive while in prison?

A recent publication—Highlights from the U.S. PIAAC Survey of Incarcerated Adults—provides information about the education and training that is received inside prison walls, in addition to providing data on the skills of incarcerated adults. This information is important because more than half of the prisoners surveyed (54 percent) were scheduled to be released within two years of their participating in PIAAC and most will likely try to enter the work force.

A look at PIAAC

The PIAAC Survey of Incarcerated Adults was conducted in 2014 and involved a representative sample of 1,300 prisoners who took assessments in literacy, numeracy, and problem solving in technology-rich environments. Most of them also completed a questionnaire that asked about their demographics and educational attainment, among other things. The results were compared to non-incarcerated adults in U.S. households who took the same assessments and completed a similar questionnaire as part of the national PIAAC program.  

The results show that 30 percent of incarcerated adults had attained less than a high school diploma—twice the percentage for U.S. households (14 percent). And more incarcerated adults scored at the lowest levels in both the literacy and numeracy assessments (see chart).


SOURCE: National Center for Education Statistics, U.S. Program for the International Assessment of Adult Competencies, U.S. National Supplement: Prison Study 2014, PIAAC 2012/14


Education and Training in Prison

The survey results show that at least some of the prisoners had opportunities to work, take academic classes, and receive job training and certification during their current incarceration. About 61 percent of those surveyed reported having a job in prison. But many prisoners reported that their jobs “never” needed them to use the type of literacy and numeracy skills which are important in the work force.

For instance, nearly half (47 percent) of incarcerated adults with jobs reported “never” reading directions or instructions as part of their current prison job, and 82 percent reported “never” working with fractions, decimals, or percentages. By comparison, in the household population surveyed as part of PIAAC, approximately 12 percent of adults reported “never” reading directions or instructions as part of their current job, and 34 percent reported “never” working with fractions, decimals, or percentages.

In terms of education, 70 percent of prisoners who were not currently taking an academic class or program said they wanted to participate in one. Among those prisoners, the programs they most wanted to participate in were to earn a certificate from a college or trade school (29 percent), a high school diploma/GED (18 percent), an Associate’s degree (18 percent), a Bachelor’s degree (14 percent), and a pre-associate education (13 percent).

However, despite the high interest in academic programs, most prisoners surveyed (58 percent) had not furthered their education during their current incarceration (see chart).


# Rounds to zero.

SOURCE: National Center for Education Statistics, U.S. Program for the International Assessment of Adult Competencies, U.S. National Supplement: Prison Study 2014, PIAAC 2012/14


Nearly a quarter (23 percent) of prisoners surveyed said they had participated in some type of job training during their current incarceration and another 14 percent were on a waiting list for such training. Among those who participating in job training, 63 percent said self-improvement was an important reason for participating and 43 percent said it was to improve their post-incarceration job opportunities (respondents could choose more than one answer).

Of those who had not participated in training and were not on the wait list, 30 percent said they were not eligible to attend, 19 percent said they were not interested in the programs offered, and 11 percent said they did not have the necessary qualifications.

The results of the 2014 PIAAC Survey of Incarcerated Adults provide a tremendous amount of information that can inform the work of researchers, policymakers, and others who are interested in the skills, education, and training of America’s prison population. Anyone interested in exploring these data can do so online through the International Data Explorer (IDE) at http://nces.ed.gov/surveys/international/ide/. For more information on PIAAC, please go to http://nces.ed.gov/surveys/piaac/.

 

Examining the workforce skills of U.S. unemployed, young, and older adults: Updated data from the PIAAC

By Stephen Provasnik and Holly Xie

Educational attainment is one of the most common measures of workforce preparation and is certainly an important indicator of whether someone is job-ready. But this one metric does not fully capture the variety of skills that can be important to potential employers. One way that NCES measures the basic workplace skills and abilities of U.S. adults is through the Program for the International Assessment of Adult Competencies (PIAAC).[1] 

PIAAC includes a number of assessments designed to evaluate real-world skills in three important areas:

  • Literacy: The literacy assessment measures the extent to which respondents can understand, evaluate, use, and engage with written text in different contexts, such as home, work, and community;
  • Numeracy: The numeracy assessment evaluates respondents’ ability to access, use, interpret and communicate mathematical information that is deemed to be important in the workplace; and
  • Problem solving in technology-rich environments: This skill area assesses respondents’ use of digital technology, communication tools, and networks to gather and evaluate information, communicate with others, and perform practical tasks.

The newly released Skills of U.S. Unemployed, Young, and Older Adults in Sharper Focus: Results from the Program for the International Assessment of Adult Competencies (PIAAC) 2012/2014 describes the workforce skill levels of unemployed adults (age 16-65), young adults (age 16-34), and older adults (age 66-74). The report, along with additional data on the NCES website, includes results from the assessments described above, as well as information about respondents’ educational background, work history, the skills they use on the job and at home, their civic engagement, and their health and well-being.

The PIAAC results show a connection between skills and employment. For instance, more than 75 percent of unemployed adults (age 16-65) had attained a high school credential or less. Roughly one-third of these adults (with a high school credential or less) scored at the lowest levels in literacy and about half scored at the lowest levels in numeracy. Overall, adults who were unemployed or out of the labor force performed worse than their employed peers in all areas of the PIAAC.


Percentage of adults age 16 to 65 at each level of proficiency on the PIAAC numeracy scale, by employment status: 2012 and 20141

1United States data are the U.S. PIAAC 2012/2014 data. PIAAC international average is calculated from the U.S. PIAAC 2012/2014 data and international data from 2012 for all other countries shown in this report. Country- and region-specific results are available at http://nces.ed.gov/surveys/piaac/results/makeselections.aspx.
SOURCE: U.S. Department of Education, National Center for Education Statistics, Program for the International Assessment of Adult Competencies (PIAAC), Skills of U.S. Unemployed, Young, and Older Adults in Sharper Focus: Results from the Program for the International Assessment of Adult Competencies (PIAAC) 2012/2014: First Look


Among young adults age 16-34, the higher the level of education completed, the larger the percentages of young adults at the highest proficiency levels in all three skill areas, and the smaller the percentages at the lowest levels. This pattern was not seen among older U.S. adults (age 66-74). Among older U.S. adults, there was no measurable difference in the percentage performing at the highest levels in literacy or numeracy between those who had a bachelor’s degree and those who had a graduate or professional degree.


Percentage of adults age 66 to 74 at each level of proficiency on the PIAAC literacy scale, by highest level of educational attainment: 2014

# Rounds to zero.
‡ Reporting standards not met. Sample size insufficient to permit a reliable estimate.
SOURCE: U.S. Department of Education, National Center for Education Statistics, Program for the International Assessment of Adult Competencies (PIAAC), Skills of U.S. Unemployed, Young, and Older Adults in Sharper Focus: Results from the Program for the International Assessment of Adult Competencies (PIAAC) 2012/2014: First Look.


Much more data can be read in the full report. Additional PIAAC data will be released later this year, including information about adults who were incarcerated.

For more information, check out this video:

 


[1] The PIAAC survey is coordinated internationally by the OECD. NCES implements PIAAC in the United States. PIAAC is a household survey administered by trained data collectors to a nationally-representative sample of adults, ages 16 through 65, in each country, in the official language(s), and in most cases, in respondents’ homes on a laptop computer. PIAAC was first conducted in 2011-2012 and results were released in October 2013 with data from 23 countries, including the United States.

The findings reported here are based on data from the first round of PIAAC and a second round conducted in 2013-2014 in the United States to collect additional data on key subgroups of the adult population. To learn more about the U.S. administration and reporting of PIAAC, as well as related data tools, see https://nces.ed.gov/surveys/piaac/.

 

Behind the degree: Direct measures of cognitive skills or reports of highest degree earned

By Heidi Silver-Pacuilla

Categories of educational attainment – or highest degree earned – are often used in social science research as an indicator of a person’s knowledge and skills. This measure is objective and readily available, easily understood by survey respondents as well as by consumers of research and survey data, strongly tied to policies (such as those promoting high school graduation and college completion rates), and widely used in the labor market by employers. Moreover, strong connections between educational attainment and positive life outcomes, such as employment, earnings, health, and civic engagement, are well established.

Yet, this measure is an imprecise indicator of the amount of knowledge and skills an individual acquired during the years of education it took to complete the degree. It also masks variation across individuals and programs of study. In addition, adults continue to acquire skills and knowledge from a variety of sources and activities over their lifetimes after completing a degree, while on the job or through employer-sponsored training, continuing education, family and household management, hobbies and interests, etc. Adults also lose fluency with skills that are not put to regular use.

The Program for the International Assessment of Adult Competencies (PIAAC) survey[i] provides direct measures of working-age adults’ cognitive skills based on their performance on literacy, numeracy, and problem-solving tasks set in real-life contexts. Performance is reported on a scale of 1-5 for literacy and numeracy and a scale of 1-3 for problem solving. It pairs these measures with a background questionnaire that asks about the use of skills at work and in daily life, work history, and other social, behavioral, and demographic indicators.


Percentage of adults age 16 to 65 at each level of proficiency on the PIAAC literacy scale, by highest level of educational attainment: 2012Percentage of adults age 16 to 65 at each level of proficiency on the PIAAC literacy scale, by highest level of educational attainment: 2012

# Rounds to zero
NOTE: Percentages of adults age 16 to 65 by highest level of educational attainment appear in parentheses. Detail may not sum to totals because of rounding.
SOURCE: U.S. Department of Education, National Center for Education Statistics, Organization for Economic Cooperation and Development (OECD), Program for the International Assessment of Adult Competencies (PIAAC), 2012.


The direct measures of cognitive skills offer researchers the ability to study actual skills rather than only using attainment of a particular degree as a general indicator of skills, and to investigate how those assessed skills relate to behaviors and life outcomes. To illustrate how directly measured skills and educational attainment are not always aligned, we can compare direct performance to highest degrees earned. In the United States, of all adults who have attained only a high school degree, 20% performed in the lowest levels (Level 1 and Below Level 1) of literacy, while 7% of adults with an associate’s degree and 5% of those with a bachelor’s degree performed at this level. At the same time, the results showed that 6% of adults with no more than a high school diploma, 14% with only an associate’s degree, and 24% with a bachelor’s degree have very high literacy skills, at Level 4 or 5 on the same scale. See the full range of educational attainment and skill performance in literacy in the chart above.

Findings such as this can help inform policy, interventions, and communication strategies to better meet the needs of the recipients.

To read more about direct measures versus educational attainment, see Chapter 8 of the OECD Survey of Adult Skills – Reader's Companion.


[i] The PIAAC survey is coordinated internationally by the OECD. NCES implements PIAAC in the United States. Results were first released in October 2013 with data from 23 countries. It is a household survey administered by trained data collectors to a nationally-representative sample of adults, ages 16 through 65, in each country, in the official language(s), and in most cases, in respondents’ homes on a laptop computer.

In the United States, the survey was first administered in 2012 and additional results, based on an expanded sample, will be released in 2015-2016. To learn more about the U.S. administration and reporting of the survey, as well as related data tools, see https://nces.ed.gov/surveys/piaac/.