Pamukkale critical thinking skill scale: a validity and reliability study

The aim of this study is to develop a valid and reliable measurement tool that measures critical thinking skills of university students. Pamukkale Critical Thinking Skills Scale was developed as two separate forms; multiple choice and open-ended. The validity and reliability studies of the multiple-choice form were constructed on two different theoretical frameworks as classical test theory and item- response theory. According to classical test theory, exploratory and confirmatory factor analyses were performed, to item-response theory, the Generalized Partial Credit Model (GPCM) for one-dimensional and multi-category scales was tested for the construct validity of the multiple-choice form of the scale. Analysis results supported the unidimensional structure of the scale. The reliability analyzes showed that the internal consistency coefficient of the scale and the itemtotal correlation values were high enough. The test-retest analysis results supported that the scale shows stability over time regarding the field it measures. The results of the item-response theory-based analysis also showed that the scale met the itemmodel fit assumptions. In the evaluation of the open-ended form of the scale, a rubric was used. Several studies were conducted on the validity and reliability of the open-ended form, and the results of the analysis provided psychometric support for the validity and reliability. As a result, Pamukkale Critical Thinking Skills Scale, which was developed in two forms, is a valid and reliable measurement tool to measure critical thinking skills of university students. The findings were discussed in the light of the literature and some suggestions were given.