Comparing DIF across math and reading/language arts tests for students receiving a read-aloud accommodation

Although testing accommodations are commonly provided to students with disabilities within large-scale testing programs, research findings on how well accommodations allow for comparable measurement of student knowledge and skill remain inconclusive. The purpose of this study was to examine the extent to which 1 commonly held belief about testing accommodations, namely that the read-aloud accommodation allows for better measurement on a math (MA) test than a reading/language arts (R/LA) test, was supported through an analysis of data from a statewide assessment program. An analysis of differential item functioning (DIF) was used to compare measurement for 2 groups of students with disabilities (i.e., those receiving a read-aloud accommodation [RA] and those not receiving an accommodation [NSD]) to that for a reference group of nonaccommodated students without disabilities. Analyses were conducted separately for MA and R/LA test sections. DIF was identified for both groups within both content areas. There tended to be more DIF identified for the RA group than for the NSD group, particularly on the R/LA test sections. This seems to indicate that the read-aloud accommodation was associated with greater measurement problems on the R/LA section than the MA section of the test.