ALL consisted of two components: a background questionnaire, about 45 minutes in length, and an assessment with about 60 minutes of assessment items (see Sample Items). Trained interviewers administered both these components to participants in their homes. Participants were selected from a nationally representative sample and in some countries/territories they received money for participating. In the United States, participants received $35 for completing the survey.
Interviewers asked respondents to respond first to the background questionnaire, which was designed to collect general information about participants (such as sex, age, race/ethnicity, education level, and labor force status) and more targeted information related to literacy practices, familiarity with information and communication technology, adult education participation and self-reported literacy skills, and health.
Once the background questionnaire was completed, the interviewer presented a booklet containing six simple tasks ("Core tasks"). Respondents who passed the Core tasks were given a booklet with a larger variety of tasks drawn from a pool of items grouped into blocks.
Each booklet contained two blocks which represented about 45 items. Overall, the assessment drew from four 30-minute blocks of Literacy items (i.e., Prose AND Document Literacy) and two 30-minute blocks of Numeracy items.
In the United States, a nationally representative sample of 3,420 adults ages 16–65 participated in ALL. Data collection for the United States took place between January and June 2003.