What is meant by “statistically sound” in 34 CRF 300.139?
There are at least two issues for consideration. One has to do with the sample size. In some instances, for example if a State chooses to disaggregate by disability categories (not a federal requirement) or report on the performance of students with disabilities in small school districts, the relatively small number of students in that category or district might raise questions about statistical soundness if generalizations are to be made about student performance. A second issue centers around the reporting of performance for students who take non-standard or modified administrations of an assessment. In such cases, there may be questions about the validity of the assessment and its comparability to the standard assessment.
