Religious Bias in Moral Development Research: A Psychometric Investigation

The present article reports two studies in which the validity of the Defining Issues Test (DI[T; Rest 1979) for conservative religious people was examined. In Study 1 we found that from 16 to 25 (of 72) DIT items had differential functioning; that is, the items were measuring a different construct for conservative religious subjects. Study 2 provided evidence that a large proportion of the differential item functioning observed in Study 1 was due to the religious connotations these items had for the religious subjects. We concluded that the DIT is not completely valid for people from some conser- vative religious cultures. Our studies join with other research in providing evidence that Kohlberg's theory of moral development is to some extent religiously and culturally limited.