The effects of test disclosure on equated scores and pass rates

Abstract

This paper examines the effects of test item disclosure on resulting examinee equated scores and population passing rates. The equating model studied was the common-item nonequivalent-populations design under Tucker linear equating procedures. The research involved simulating disclosure by placing correct answers of "disclosed" items into response vectors of selected examinees. The degree of exposure the disclosed items received in the population was manipulated by varying the number of items disclosed and the number of examinee records receiving the correct answers. Other factors considered among the 10 experimental conditions included the characteristics of the disclosed items (difficulty of disclosed items and whether they were anchor or nonanchor test items) and the ability level of the subgroup receiving the disclosed items. Results suggest that effects of disclosure depend on the nature of the released items. Specific effects of disclosure on particular examinees are also discussed. Index terms: equated scores, licensing exams, passing rates, simulated disclosure, test disclosure.