In this context, post hoc study of older trials suggests that the benefit risk ratio for prophylactic aspirin generally becomes more favorable at >10% esti- However, the relative benefits of aspirin, specifically in pre- venting nonfatal MI and perhaps stroke (with a trend to lower mortality) have been less evident in more recent trials.S4.6-9,S4.6-16,S4.6-17,S4.6-20 Similarly, in these recent trials, the estimated ASCVD risk has generally exceeded the actual risk observed during These recent data are the rationale for the lower COR for prophylactic aspirin in the present guideline (Class IIb) and the removal of a specific PCE risk threshold as an inclusion criterion for aspirin consideration. These changes reflect the need to instead consider the totality of available CLINICAL STATEMENTS AND GUIDELINES evidence for ASCVD risk [inclusive, where appro- priate, of risk-enhancing factors, such as strong family history of premature MI, inability to achieve lipid or BP or glucose targets, or significant eleva- tion in coronary artery calcium scoreS4.6-21 ] and to also tailor decisions about prophylactic aspirin to patient and clinician preferences. Depending on risk factors present, a given patient and his/her clinician may decide that lowering the risk of MI (which has potentially serious long-term conse- quences not captured by clinical trials of 5 to 10 years duration) is worth a slight excess risk of seri- ous bleeding. Recent trials show that absolute risk for ASCVD events typically exceeds that of bleed- ing and, although the gap of relative benefit to relative harm for aspirin has narrowed, the num- ber needed to treat to prevent an ASCVD event remains lower than the number needed to harm to cause bleeding. 