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International Adult Literacy Survey (IALS)


Some of the key concepts related to the IALS literacy assessment are described below.

Literacy. The ability to use printed and written information to function in society, to achieve oneís goals, and to develop oneís knowledge and potential.

Prose Literacy. The ability to read and use texts of varying levels of difficulty that are presented in sentence and paragraph form, including editorials, news stories, poems, and fiction.

Document Literacy. The knowledge and skills required to locate and use information contained in formats such as job applications, payroll forms, transportation schedules, maps, tables, and graphics.

Quantitative Literacy. The knowledge and skills required to apply arithmetic operations, either alone or sequentially, to numbers embedded in printed materials, such as balancing a checkbook, calculating a tip, completing an order form, or determining the amount of interest on a loan from an advertisement.

Literacy Scales. The three scales used to report the results for prose, document, and quantitative literacy. These scales, each ranging from 0 to 500, are based on those established for the Young Adult Literacy Assessment, the DOLís Workplace Literacy Survey, and the National Adult Literacy Survey. The scores on each scale represent degrees of proficiency along that particular dimension of literacy. The scales make it possible not only to summarize the literacy proficiencies of the total population and of various subpopulations, but also to determine the relative difficulty of the literacy tasks administered in IALS.

The literacy tasks administered in IALS varied widely in terms of materials, content, and task requirements, and thus in difficulty. A careful analysis of the range of tasks along each scale provides clear evidence of an ordered set of information-processing skills and strategies along each scale. To capture this ordering, each scale was divided into five levels that reflect this progression of information-processing skills and strategies: Level 1 (0 to 225), Level 2 (226 to 275), Level 3 (276 to 325), Level 4 (326 to 375), and Level 5 (376 to 500). Level 1 comprised those adults who could consistently succeed with Level 1 literacy tasks but not with Level 2 tasks, as well as those who could not consistently succeed with Level 1 tasks and those who were not literate enough to take the test at all. Adults in Levels 2 through 4 were consistently able to succeed with tasks at their level but not with the next more difficult level of tasks. Adults in Level 5 were consistently able to succeed with Level 5 tasks. The use of three parallel literacy scales makes it possible to profile and compare the various types and levels of literacy demonstrated by adults in different countries and by subgroups within those countries.