NAEP endeavors to include as many sampled students as possible in the assessment, including students with disabilities (SD) and English language learners (ELL), and has established specific inclusion goals: 95 percent of all sampled students and 85 percent of sampled students identified as SD or ELL. Students are selected to participate in NAEP based on a sampling procedure designed to yield a sample of students that is representative of students in all schools nationwide and in public schools within each state and TUDA district. Inclusion rates were computed for each state/jurisdiction participating in the 2011 assessment and compared to NAEP inclusion goals. Three inclusion percentages were computed for each state/jurisdiction. An overall inclusion percentage represents included students as a percentage of all students sampled within the state/jurisdiction. In addition, separate percentages were computed to signify included students as a percentage of the state/jurisdiction sample that was identified as SD or ELL. Each inclusion rate is calculated as the percentage of sampled students who were included in the assessment (i.e., were not excluded).
Inclusion percentages are sample estimates that are associated with a measure of uncertainty or margin of error. Confidence intervals quantify this uncertainty due to sampling, resulting in interval estimates of the inclusion percentages. Therefore, methods appropriate for constructing confidence intervals for percentages were used to determine upper and lower confidence bounds around the inclusion point estimates.
When determining whether each state/jurisdiction met the NAEP inclusion goals, the confidence intervals were used, rather than just the point estimates. In other words, if the inclusion goal, whether 95 percent or 85 percent, fell within the corresponding confidence interval, the state/jurisdiction was considered as having met the goal. Therefore, states/jurisdictions for which the upper bound of the confidence interval was less than 95 percent did not meet the overall inclusion goal.
Read more about the NAEP inclusion policy, including exclusion rates from current and previous assessments in all subject areas.