The reliabilities of six item bias indices were investigated
for each of the eleven tests of the Iowa Tests
of Basic Skills, using random samples of fifth-grade
students. The reliability of an index was defined as its
stability from one randomly equivalent group to another.
Both racial and sexual bias were considered. In
addition, correlations among bias indices were investigated.
The results indicate that the item bias indices
investigated were fairly unreliable when based on
sample sizes of 200 minority and 200 majority examinees.
Consequently, this study suggests that, with
sample sizes of about 200, the use of item bias indices
to screen achievement test items cannot be expected to
lead to consistent decisions about which items are