This U.S. Department of Education's National Center for Education Statistics has released the household and prison public-use data files for the 2003 National Assessment of Adult Literacy and the 1992 National Adult Literacy Survey. The accompanying 2003 National Assessment of Adult Literacy Public-Use Data File User's Guide (1.7 MB) explains how the data was collected and how it can be analyzed and includes codebooks for the datasets as well as instructions for using AM Software to analyze the data.
Restricted use files are available with a complete set of the variables collected on the NAAL. Users must apply for an NCES license to access restricted data.
The data derive from one-on-one interviews with adults in homes and prisons across the United States. Household interviews were conducted in 2003 and prison interviews were conducted in 2004. The household sample was multi-stage and selected on the basis of Census-defined geographical areas, while the prison sample was institution-based.
To keep participant burden to a minimum, NAAL administers only a fraction of the assessment items on each scale to each participant—too few items to produce accurate scale scores for each adult. To account for this, marginal maximum likelihood (MML) models are used to estimate proficiencies for the population and for groups within the population based upon responses to questions that were answered. The AM Software provides these estimates.
The 2003 combined household-prison public use file (5.3 MB) includes background data and responses to test items that can be used to estimate proficiency on the prose, document, and quantitative scales using a marginal maximum likelihood model. There are 19,258 completed interviews in this file. An additional 456 adults could not be interviewed and tested because of language barriers or for cognitive reasons (such as Alzheimer's or dementia). These adults are not included in the data file. A separate 2003 public-use file (5.3 MB) permits estimates of proficiency on the health literacy scale.
The 1992 combined household-prison public use file (8.5 MB) also includes background data as well as test items that can be used to estimate proficiency. Background variables that are the same in both years were given the same name.
The NALS 1992 restricted-use file (RUF) with rescaled literacy scores for household and prison (found here) contains individual unit data including both responses to the background questionnaire and the cognitive assessment from the NALS data collection, completed in 1992. The file contains rescaled plausible values for literacy and some trend background questionnaire items, including key demographics and items that were exactly the same between NALS and PIAAC, to allow for trend analysis with the U.S. Program for the International Assessment of Adult Competencies (PIAAC) data. The RUF with rescaled scores can be accessed through a restricted use license agreement with the National Center for Education Statistics.