1549
Overall , in high - risk patients , warfarin is superior to aspirin in preventing strokes , with a relative risk reduction of 36 % .
 warfarin, aspirin, strokes
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 warfarin, aspirin, strokes