Since its inception in 1969, NAEP has served the important function of measuring our nation's educational progress by regularly administering various subject area assessments to nationally representative samples of students. The existence of the two national assessment programs—long-term trend NAEP and main NAEP—makes it possible to meet two important objectives:
measure student progress over time, and
as educational priorities change, develop new assessment instruments that reflect current educational content and assessment methodology.
The NAEP long-term trend assessments in reading and mathematics were administered throughout the nation in the 2007–2008 school year to samples of students aged 9, 13, and 17. Because the long-term trend program uses substantially the same assessments decade after decade, it has been possible to chart educational progress since 1971 in reading and 1973 in mathematics.
The long-term trend assessment was updated in several ways in 2004. Outdated material was replaced, accommodations for students with disabilities (SD) and for English language learners (ELL) were allowed, and administration procedures were modified. A special bridge study was conducted in 2004 to evaluate the effects of these changes on the trend lines. The study involved administering both the original and revised formats of the assessments to determine how the revisions may have affected the results.
It was determined that changes in the assessment format were not the source of differences because data from the two assessments were successfully linked using a common-population procedure: the portions of the original assessment and revised assessment samples that comprised students who were not identified as students with disabilities or English language learners were randomly equivalent samples. Therefore, differences in 2004 results from the original and revised versions could be attributed solely to the inclusion of students who would have been excluded if accommodations had not been offered in the revised version. These differences were comparable to those seen when accommodations were first introduced in the main NAEP assessments. In particular, for 9-year-olds, 2004 results overall and for male students were lower in the revised assessment format than in the original format. This is consistent with expectations, given the increased inclusion in the revised assessment results of students with disabilities and English language learners who otherwise would have been excluded from the assessment.
The common-population procedure used in 2004 ensures a powerful and valid link to both the 2004 original assessment results and to assessment results prior to 2004 which were based upon the original assessment format and procedures. It was therefore concluded that, bearing in mind the differences in the populations of students assessed (accommodated vs. not accommodated), future assessment results could be compared to those from earlier assessments based on the original version. Read a full description of the results of the bridge study in NAEP 2004 Trends in Academic Progress: Three Decades of Student Performance in Reading and Mathematics
The reading and mathematics long-term trend assessments are composed of multiple-choice and constructed-response questions. Students taking the 2008 long-term trend assessment were given a background questionnaire to complete. The questionnaire provides NAEP staff with information on students' demographic characteristics, classroom experiences, and educational support.
Learn more about procedures used as part of the 2008 long-term trend assessment.