Historically, access ramps were part of a package of testing accommodations for students with significant physical impairments. If students with disabilities can't get to the testing room, they certainly can't demonstrate what they know or can do. Testing accommodations facilitate access to a test for students with a wide range of disabilities just like a ramp facilitates access to a building for students with physical disabilities. The tests that students are required to take are designed to measure some specific target cognitive skills or abilities, such as mathematical reasoning and computations, but almost always assume that students have the skills to access the test, such as attending to instructions, reading story problems, and writing responses. Valid testing accommodations, just like an access ramp, should be designed to reduce problems of access to a test and enable students to demonstrate what they know and can do with regard to the skills or abilities the test is targeting.
Educators then have a more accurate or valid picture of their abilities in the area tested.
Most states now have guidelines that define testing accommodations and that identify acceptable accommodation practices for students with disabilities. But because of a lack of experimental studies, little has been known about the effects of accommodations on test scores. To address that need, Elliott and Kratochwill and several graduate students are studying the use and effectiveness of testing accommodations packages being provided to a sample of 100 fourth-graders. Midway through a three-year study funded by the U.S. Department of Education's Office of Special Education and Rehabilitative Services, Elliott and Kratochwill have determined that more than 75 percent of the testing accommodations packages they examined with these students have a moderate to large effect on test scores earned on complex mathematics and science performance tasks. On average, the resulting effect size, when comparing accommodated scores to unaccommodated scores for the same type of student was .83.