Comparison of item analysis results of Korean Medical Licensing Examination according to classical test theory and item response theory

Abstract

The results of the 64th and 65th Korean Medical Licensing Examination were analyzed according to the classical test theory and item response theory in order to know the possibility of applying item response theory to item analys and to suggest its applicability to computerized adaptive test. The correlation coefficiency of difficulty index, discriminating index and ability parameter between two kinds of analysis were got using computer programs such as Analyst 4.0, Bilog and Xcalibre. Correlation coefficiencies of difficulty index were equal to or more than 0.75; those of discriminating index were between - 0.023 and 0.753; those of ability parameter were equal to or more than 0.90. Those results suggested that the item analysis according to item response theory showed the comparable results with that according to classical test theory except discriminating index. Since the ability parameter is most widely used in the criteria-reference test, the high correlation between ability parameter and total score can provide the validity of computerized adaptive test utilizing item response theory.