Objectives:Quality of life (QoL) is a major outcome parameter in dementia care. Self-ratings are considered the best way to evaluate QoL, but staff-ratings also provide valid results. In particular, the discrepancies between self-ratings and staff-ratings are underrepresented. The aim was to identify characteristics of people with dementia that improve the probability of completing a self rating QoL instrument on the ‘Quality of Life – Alzheimers’ Disease’ (QoL-AD). Additionally, a level of agreement was set between self-rated and staff-rated QoL-AD and possible influencing factors.