Assessment Accommodations Research: Considerations for Design and Analysis. Technical Report 26.

This monograph reviews issues in research on the effects of using accommodations for students with disabilities who are included in educational assessments, particularly state and district assessments. Following an introductory overview, a section provides background on the need for good research on accommodations. The paper then defines commonly used terms and considers the purpose of assessment accommodations. Identification of issues in accommodations research considers comparability of scales administered under standard and nonstandard conditions, comparability of scores, and determination of cutoff scores. The paper explains three general analytic strategies in the context of accommodations research: item response theory, factor analysis, and criterion related analyses. Also considered are group research design considerations such as sampling and sample size. A major section explains four research designs in order from the most optimal to the least optimal. Other research designs considered include single subject, withdrawal-reversal, multiple baseline, multiple probe, changing criterion, and comparative designs. The paper concludes with four recommendations to researchers: (1) focus on the accommodation/s of most interest; (2) focus on those students who comprise the largest part of the population with disabilities; (3) if comparing groups, one group should be students without disabilities; and (4) collect other measures to help clarify findings. (Contains 30 references.) (DB)