Is the difference real, is the difference relevant: the minimal detectable and clinically important changes in the Montreal Cognitive Assessment

Highlights • Stroke trials with cognitive outcomes are increasingly common. Many of these trials recruit in the acute stroke period and so an understanding of the properties of cognitive scores in this time window is important.• The Montreal Cognitive Assessment (MoCA) mean scores at admission and 6-month follow-up were 22 and 25, respectively among 1131 stroke survivors.• MoCA exhibited good reliability with a minimal detectable change of 5.1 points.• The minimal clinically important difference for MoCA varied by method between 1 and 2 MoCA points. Subgroup analyses showed differences based on factors like previous stroke, reperfusion treatment, and age, highlighting nuanced clinical implications.