[Content validity and inter-rater reliability of the Cognitive Fluctuation Inventory]

The Cognitive Fluctuation Inventory (CFI) was developed to evaluate cognitive fluctuation in patients with dementia with Lewy bodies (DLB). The objective of this study was to assess the content validity and inter-rater reliability of the CFI.Nine specialists in DLB treatment were invited to participate in the survey to assess the content validity of the CFI. They were asked to assess the relevance and comprehensibility of the question items. In the validation study, inter-rater reliability was assessed using the intraclass correlation coefficient (ICC).Regarding content validity, all nine specialists considered the main question and sub-questions to be relevant to cognitive fluctuation in patients with DLB. Eight out of nine specialists considered the CFI to be a comprehensive measure for detecting cognitive fluctuation in patients with DLB. In the analysis, which used data from 29 patients and their caregivers, the ICC of the CFI was 0.746, which suggests good inter-rater reliability.We found that the CFI showed good content validity and inter-rater reliability for evaluating cognitive fluctuation in patients with DLB.