The June 2001 report of the Comprehensive Tests of Basic Skills (CTBS) has been updated to reflect new information received from the Maryland State Department of Education (MSDE) regarding the calculation of the median percentile ranks for each subtest.

The new calculation requirements include scores of students who were previously excluded by MSDE because of extended time accommodations provided through their Individualized Education Program (IEP) or the requirements under Section 504 of the Rehabilitation Act of 1973. As a result of the change in calculation, the 2001 results reported for the Montgomery County Public Schools (MCPS) and individual schools have changed in some subject areas and grade levels [see link to report below].

During the 2001 administration of the CTBS, there were 32,758 students in Grades 2, 4, and 6 who took the exam, of whom 2,707 students (8.2 percent) were given extended time accommodations because of their IEP and 303 students (0.9 percent) who received similar accommodations because of Section 504. MSDE previously had excluded the scores of these students in the calculation of median percentile rank. (The median percentile rank is used for comparative purposes among schools and school systems for each subtest, including comparisons with national norms.)

In a report to the Board of Education, Dr. Jerry D. Weast, superintendent of schools, said the “manner in which the state changed the calculation methodology and informed school districts is a matter of dispute.” The superintendent had earlier reported to the Board of Education that the state’s explanation of the changes in calculating the median percentile rank was inconsistent. “At this time, the calculation methodology still is not entirely clear,” he said.

Under MSDE’s revised calculation requirements, for example, not all students with accommodations were included. Students who received accommodations for the use of a calculator were excluded for the first time. There has been no explanation from MSDE for the distinction between the two sets of accommodations (extended time and calculators). Dr. Weast said the school system is awaiting direction from MSDE about the requirements for the 2002 administration of the CTBS, which takes place next month.

The revised results still demonstrate that the school system continues to perform well above the national data in all of the subtests for language, reading, and mathematics on the CTBS. Nonetheless, the impact of the change in median percentile ranks has the effect of lowering some results by as many as 13 points (Grade 2 language). Conversely, in several instances the results stayed the same or increased.

Dr. Weast said “the fact that the changes are due to a difference in calculation methodology means that the revised median percentile ranks for 2001 become the benchmarks for future comparisons.”

The attached PDF file provides the revised CTBS results for each individual school. Principals had received previously the individual student results, which are not affected by the calculation of the median percentile ranks. Individual student reports that were mailed earlier this year contained comparative data, including the median percentile ranks based on the original report. Due to budgetary constraints and the lateness of the new information from MSDE about the change in calculation, the individual student reports will not be revised this year. The individual student reports for 2002 will contain the new information, with an appropriate explanation.

Dr. Weast said the “CTBS remains a fundamental component of the overall accountability program for Montgomery County, especially given the controversy regarding the Maryland School Performance Assessment Program (MSPAP).” He said the new method for calculating the final scores “does not change the usefulness of the assessment in providing students, parents, teachers, and principals with individual student data about important instructional areas at pivotal points in the educational process.”

The revised report is available at the link below.