Using Rasch analysis to construct a Clinical Problem-Solving Inventory in the dental clinic: a case study

A 28-item inventory was developed to measure the clinical problem-solving abilities of 3rd and 4th year dental students. The judgments of 57 expert raters (dental-school faculty) from four dental schools used the inventory to evaluate 183 dental students on a 5-point rating scale. The Rasch measurement model was employed to examine the psychometric properties and construct validity of this inventory. In this study, fit statistics identified the "noise" in the data and residual analysis assisted in extracting a meaningful structure. The study results indicate that the Rasch measurement model appeared to be a useful method for use in producing a unidimensional instrument. All five rating categories were used in a coherent manner, and four discernable levels of clinical problem-solving ability were identified. After removal of four repetitious items, a version of the Clinical Problem-Solving Inventory was finalized that could serve as a criterion measure for validating the use of a critical thinking test on the Dental Admission Test.