The aim of this study is to study the validity and reliability of the cognitive flexibility scale (CFS) for a Turkish adaptation. For the factor analysis and reliability studies, data was collected from 370 high school students (160 female, 210 male, Xage=16.15, ss=1.33). In addition, data was collected from 392 adolescents for scale dependant reliability (218 female, 174 male, Xage=16.11, ss=1.14). The results of the completed studies reveal that the CFS, which consists of 11 items, explains 43%, of the variance in the total groups, and that CFS is unidimentional. In addition, the internal coefficient (α) parameters of the measuring tools in the total group were .74. A significant difference was found in the 27 percentile of sub and top groups with regard to all CFS items. In a criterion referenced reliability study, significant correlations were found between CFS and problem solving inventory sub scales and their total score.

Keywords: Cognitive flexibility, Validity, Reliability, Self-efficacy belief, Problem solving