Delivering person-centred care to those with advanced dementia in nursing homes presents numerous challenges. When caring for people with dementia, frontline staff may face situations ranging from insufficient symptom management to a compromised quality of life. Using systematic assessment instruments have been described as ways for potentially enhancing person-centred care and caring for people with dementia. However, in Switzerland, specific symptom recognition measures for people with dementia remain unavailable, and their efficacy remains untested. This thesis presents the translation and psychometric testing of a measure developed for assessing common symptoms in people with dementia. The Integrated Palliative Care Outcome Scale for People with Dementia (IPOS-Dem) underwent a six-step translation and cultural adaptation to Swiss-German nursing home settings through the use of easy-read principles. However, its inter-rating reliability among frontline staff was found to be suboptimal, with kappa values ranging between .15 (95% CI .08-.22) and .38 (95% CI .30-.48). Although aggregate IPOS-Dem scores might serve research needs when averaged across two measures, its application remains a central component of a complex nursing intervention trialled in a broader project. The unique challenges of researching this context and demographic influenced the overarching project’s design and the subsequent psychometric evaluation of IPOS-Dem. IPOS-Dem can improve caring for people with dementia and can be recommended for research purposes. For clinical practice, the development of a manual to help discern the different symptoms can be recommended. The development and application of tools like IPOS-Dem underscore the global urgency to enhance caring for the rapidly growing population of people with dementia. The insights from this thesis not only lay the groundwork for future refinement of IPOS-Dem, but also emphasise the importance of the rigorous evaluation of clinical tools. The collaboration with ProInfirmis and adoption of easy-read principles further highlight the potential to democratise and improve healthcare communication, which is crucial for vulnerable patient populations.