The ability of nursing staff to assess and evaluate behavioral and psychological symptoms of dementia (BPSD) to determine when intervention is needed is essential. In order to assist with the assessment process, the current use of the Neuropsychiatric Inventory Nursing Home version (NPI-NH) is internationally accepted. Even though the NPI-NH is thoroughly validated and has several advantages, there are also various challenges when implementing this system in practice. Thus, the aim of this study was to explore clinical reasoning employed by assistant nurses when utilizing the NPI-NH as a tool to assess frequency and severity of BPSD in individuals with advanced dementia.

Twenty structured assessment sessions in which assistant nurses used the NPI-NH were audio recorded and analyzed with a discourse analysis focusing on the activities in the communication.

Four categories were identified to convey assistant nurses' clinical reasoning when assessing and evaluating BPSD using the NPI-NH: considering deteriorations in ability and awareness, incorporating individual and contextual factors, overcoming variations in behaviors and ambiguous formulations in the instrument, and sense-making interactions with colleagues.

The NPI-NH served as a supportive frame and structure for the clinical reasoning performed during the assessment. The clinical reasoning employed by assistant nurses became a way to reach a consensual and broader understanding of the individual with dementia, with the support of NPI-NH as an important framework.