PurposeDementia prevalence is increasing worldwide. With the emergence of digital rehabilitation, serious digital games are a potential tool to maintain and monitor function in people living with dementia. It is unclear however whether games can measure changes in cognition. We conducted a scoping review to identify the types of outcomes measured in studies of serious digital games for people with dementia and cognitive impairment.MethodsWe included primary research of any design including adults with cognitive impairment arising from dementia or another health condition; reported data about use of serious digital games; and included any cognitive outcome. We searched Medline (via EBSCO), PsycInfo, CINAHL, Web of Science, from inception to 4th March 2024 and extracted study characteristics.ResultsWe reviewed 5899 titles, including 25 full text studies. We found heterogeneity in domains and measures used: global cognition (n = 15), specific cognitive processes (n = 13), motor function (n = 5), mood (n = 6), activities of daily living (n = 5), physiological processes (n = 4) and quality of life (n = 2). Use of outcome measurement tools was inconsistent; the most frequently used measures were the Montreal Cognitive Assessment (n = 8), the Mini-Mental State Examination (n = 7), and the Trail Making Test (n = 7). Nine studies used in-game measures, most of which were related to game performance.ConclusionWe found very few studies with assessment of cognition within the game. Studies of serious games for people with dementia and cognitive impairment should develop digital outcome tools based on recommendations in Core Outcome Sets, to increase consistency between studies. Fewer than half of the studies we identified used in-game measures, most of which were related to game performance, indicating that digital measures of cognition within serious digital games is a largely unexplored research area.Only eight out of 25 included studies used measurements tools recommended in Core Outcome Sets for studies of people living with dementia.Given the heterogeneity of measures identified in this review, critical appraisal of relevant outcome measures would be the next step in determining suitable measures for use in future research.Following critical appraisal, exploration of digital measures of cognition is needed to determine their integration into serious games, and whether existing tests can be digitised and administered remotely whilst retaining psychometric properties.