PARA Accessible Reading Assessment Reports: Examining Differential Item Functioning in Reading Assessments for Students With Disabilities


A report examining group differences between students with disabilities and students without disabilities using differential item functioning (DIF) analyses in a high-stakes reading assessment. Results indicated that for grade 9, many items exhibited DIF and these were more likely to be located in the second half of the assessment subscales. After accounting for reading ability, when compared to their non-disabled peers, students with disabilities consistently under-performed on items located in the second half relative to the items located in the first half. These results were seen in grade 9 for data from two different states, but these results were not seen for grade 3. This study has several limitations to the data. There was no access to information about the testing accommodations that students with disabilities might have received, and no information about the type of disabilities. Results of this study can shed light on potential factors affecting the accessibility of reading assessments for students with disabilities, in an ultimate effort to provide assessment tools that are conceptually and psychometrically sound for all students.


January 2007 
Partnership for Accessible Reading Assessment (PARA)
National Center on Educational Outcomes (NCEO)


  • Specific life stage
    • Children
    • Adolescents and young adults
  • Educational accountability and assessment
    • Accessibility & Accommodations