I am looking for information for some extended family members.
A medical procedure has a 4% chance of stroke per year over 5 years. One family member has said that that is a 20% chance of stroke over all (5*4%). Others argue that it is less because 4% each year is smaller. I am not sure how to frame this question in order to get an accurate answer. Is the chance of something happening being 4% a year for 5 years the same as say an instantaneous 20% chance of something happening?