Tippets, E., & Michaels, H. (1997, March). Factor structure invariance of accommodated and non-accommodated performance assessments . Annual meeting of the National Council on Measurement in Education (NCME), Chicago, IL, United States.

Students took the test in one of five different ways: Group 1: standard administration of the test; Group 2: students received a reading accommodation only; Group 3: students received a combination of reading and extended time accommodations; Group 4: students received combination of reading and dictated response accommodations; Group 5: students received a combination of the reading, dictated response, and extended time accommodations.

A sample of Maryland (U.S.) students taking the 1996 MSPAP clusters was used as the control population (group 1). The other groups of students were those who took the 1996 MSPAP using the accommodations listed above. Students in grades 3, 5, and 8 were represented in the sample. Two hundred (200) students from each grade were represented in the control population.

The Maryland School Performance Assessment Program (MSPAP), a criterion-referenced performance assessment, was used as the dependent variable. More specifically, factor analyses of the reading and language usage sections of the MSPAP were conducted.

Factor structures for accommodated and non-accommodated students were generally the same. However, there were significant differences in the performance of different groups. Generally, groups 3 and 5 did significantly better than the other groups in both reading and language usage. Within the third grade population, groups 1 and 5 performed significantly better than 2 and 4, and group 3 performed significantly better than groups 2, 4, and 5 in reading. For third grade English language arts, groups 1 and 5 performed significantly better than groups 2 and 4, and group 3 performed significantly better than all other groups. In grade 5 reading, groups 1 and 5 performed significantly better than groups 2 and 4, group 5 performed significantly better than groups 1, 2, and 4 and group 3 out-performed all other groups. For eighth grade reading and English language arts, the non-accommodated group out-performed the accommodated groups.