Acute interventions and secondary prevention strategies of proven benefit based on level I evidence.

The number needed to treat (NNT1) to prevent one stroke patient dying or becoming dependent (acute stroke), or to prevent one fatal or non-fatal stroke (secondary prevention), per year, are given. All figures are approximate and derived from previous analyses, the Cochrane database, or individual trials if these are the only data available. Modified from Donnan et al. [2], aNNT for survival with mRS≤3. bCalculations based on mean follow-up of 3.9 y in PROGRESS (NNT3.9 = 25) and median 4.9 y in SPARCL (NNT4.9 = 45). ARR, absolute risk reduction; ICH, intracerebral haemorrhage; IS, ischaemic stroke; NNT, number needed to treat; RRR, relative risk reduction.