This study developed a test entitled Clinical Critical Thinking Skills (CCTS) by using item response theory (IRT)
and examined its validity. In the development stage, data obtained from a convenience sample of 627 undergraduate
nursing students were analyzed using a discrimination and difficulty index with the TestAn 1.0 program.
In the evaluation stage, data from a convenience sample of 284 nursing and non-nursing students were
analyzed using a discrimination and difficulty index with the BILOG-MG program. Criterion validity was verified
by the group comparison method. Five items received low discrimination index scores according to the IRT results.
In terms of the criterion validity, CCTS scores differed according to major (t=2.21, p=0.028), location of
high school (F=4.35, p=0.014), clinical experience (t=5.66, p=0.004), and grade point average (F=7.17, p<
0.001). The CCTS can be used to measure critical thinking skills in the clinical setting