But other experts called the findings inconclusive even though there is no suggestion that giving aspirin could do any harm. Some concern has emerged that aspirin, which can cause internal bleeding, could be harmful to stroke victims.
Two trials of 40,000 stroke patients - one involving 36 countries and one based in China - found aspirin slightly decreased the rate of death in the first two weeks after a stroke.
Peter Sandercock, of the University of Edinburgh, who helped co-ordinate the international trial of 20,000 patients, said: "It's good to find the cheapest, easiest treatment is the best."
The study, published in the Lancet, compared aspirin with heparin, another drug used to help prevent blood clots. It found heparin slightly increased the risk of haemorrhagic stroke.Reuse content