The reliability and validity of the Turkish version of the Neuropsychiatric Inventory-Clinician

Background/aim: The Neuropsychiatric Inventory-Clinician (NPI-C) scale is one of the best-known scales for evaluating the behavioral and psychological symptoms of dementia. This study aimed to assess the reliability and validity of the Turkish version of the NPI-C scale in patients with Alzheimer disease (AD). Materials and methods: The NPI-C scale was administered to 125 patients with AD. For reliability, both Cronbach's α and interrater reliability were analyzed. The Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD) scale was applied for validity and, in addition, the Mini Mental State Examination (MMSE), Instrumental Activities of Daily Living (IADL) scale, and Disability Assessment of Dementia (DAD) scale were completed. Results: The Turkish version of the NPI-C scale showed high internal consistency (Cronbach's α = 0.75) and mostly good interrater reliability. Assessments of validity showed that the NPI-C and corresponding BEHAVE-AD domains were found to be significantly correlated, between 0.925 and 0.195. Moreover, the correlations between NPI-C and MMSE were significant for all domains except the dysphoria, anxiety, and elation/euphoria domains. When we conducted a correlation analysis of NPI-C with IADL, all domains were statistically significantly correlated except aggression, anxiety, elation/euphoria, and dysphoria. Conclusion: The Turkish version of the NPI-C scale was found to be a reliable and valid instrument to assess neuropsychiatric symptoms in Turkish elderly subjects with AD.