Objective: The National Agency for Automotive Safety and Victims’ Aid score original (NASVA score-O) is an evaluative assessment for patients in an unresponsive wakefulness state (UWS). The objective was to examine the difficulty of each sub-item of the NASVA score-O and its suitability for the assessment of patients in a UWS. Methods: The participants were 134 patients in a UWS (96 men, 38 women; age range at admission, 9-83 years). The scaled NASVA score-O, an outfit mean square (MNSQ), and an infit MNSQ for each sub-item using Rasch modeling were calculated. The 48 sub-items were arranged in order of the score of the item measures, and a difficulty map was created. The suitability of the 48 sub-items was analyzed using the outfit and the infit MNSQs. Results: Ten sub-items were classified as misfits, and the item measure of five sub-items was -5.1 points. Conclusions: Medical staff and family members may be able to set suitable short-term goals and adapt caregiving methods to the recovery process using the difficulty map. It is necessary to remove 10 misfit sub-items, modify the questions, or create an interpretation manual and to reanalyze it without the five sub-items with negative points.