Stroke Training and Awareness Resources (STARs)
Benefits of aspirin for 100 stroke / TIA patients
- Without aspirin 25 patients might have a stroke during 1st year after a TIA or ischaemic stroke
- With aspirin only 20 might have a stroke (i.e. a 20% relative risk reduction – 25-20/25 x100% = 20%)
- Of the 25 who would have had a stroke, 5 avoid a stroke due to taking aspirin
- 80 did not have a stroke
- Treat 100 patients for a year and benefit 5
- Treat 20 patients for a year with aspirin and prevent one of them having a stroke (i.e. number needed to treat = 20)
- Each patient has a 1 in 20 chance of benefit from taking aspirin for the year
