Psychometric Properties of Dyslexia Knowledge Measurement

• In Event: Becoming Literate: The Science of Teaching Reading

Abstract

Given rapid growth in educational policies targeting educators’ knowledge of dyslexia, this study explored the technical adequacy of a common instrument for measuring that knowledge. The responses of 1,141 preservice teachers were scored in three ways: polytomously with the original 4-point Likert scale, dichotomously as true-false, and dichotomously as though the options were multiple choice. An exploratory factor analysis suggested at least one-third of the items needed to be removed. Confirmatory factor analyses suggested a one-factor model with polytomous scoring had the best fit to the data, but only 6 items loaded. All models demonstrated unacceptable internal consistency reliability (<0.70). Because no technically adequate version of the measure was identified, questions remain about basing policy on scores from these instruments.

Authors

• Deborah K. Reed, University of Tennessee

• Huibin Zhang, University of Tennessee