Simulations were conducted to examine the effect of differential item functioning (DIF) on measurement consequences such as total scores, item response theory (IRT) ability estimates, and test reliability in terms of the ratio of true-score variance to observed-score variance and the standard error of estimation for the IRT ability parameter. The…

To efficiently assess multiple psychological constructs and to minimize the burden on respondents, psychologists increasingly use shortened versions of existing tests. However, compared to the longer test, a shorter test version may have a substantial impact on the reliability and the validity of the test scores in psychological research and…