Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
All-cause mortality
[71] RCT 3-armed trial	1587 people with New York Heart Association (NYHA) class II to IV	Rate of mortality median follow-up of 21 months 94/523 (19%) with aspirin 92/540 (17%) with warfarin	HR 0.98 (warfarin v aspirin) 95% CI 0.85 to 1.13 P = 0.75 The RCT was terminated early because of slow enrolment (1587 people randomised rather than the planned 4500 people) and may have been underpowered to detect a clinically important difference Results should be interpreted with caution		Not significant
[71] RCT 3-armed trial	1587 people with NYHA class II to IV	Rate of mortality median follow-up of 21 months 96/524 (18%) with clopidogrel 92/540 (17%) with warfarin	HR 0.92 (warfarin v clopidogrel) 95% CI 0.69 to 1.23 P = 0.58 The RCT was terminated early because of slow enrolment (1587 people randomised rather than the planned 4500 people) and may have been underpowered to detect a clinically important difference Results should be interpreted with caution		Not significant
Death, MI, and stroke
[66] RCT 3-armed trial	279 people, 70% with NYHA functional class III	Rate of combined outcome of death, MI, and stroke mean follow-up of 27 months 29/91 (32%) with aspirin (300 mg/day) 23/89 (26%) with warfarin	Reported as not significant (aspirin v warfarin) P value not reported		Not significant
Composite outcome including all-cause mortality
[71] RCT 3-armed trial	1587 people with NYHA class II to IV	Rate of composite outcome of death, non-fatal MI, or non-fatal stroke 108/523 (21%) with aspirin 106/540 (20%) with warfarin	HR (warfarin v aspirin) 0.98 95% CI 0.86 to 1.12 P = 0.77		Not significant
[71] RCT 3-armed trial	1587 people with NYHA class II to IV	Rate of composite outcome of death, non-fatal MI, or non-fatal stroke 113/524 (22%) with clopidogrel 106/540 (20%) with warfarin	HR (warfarin v clopidogrel) 0.89 95% CI 0.68 to 1.16 P = 0.39		Not significant
[67] RCT	197 people aged 20 to 75 years with NYHA class II to IV caused by either previous MI or idiopathic dilated cardiomyopathy	Time to the primary combined outcome of non-fatal stroke, peripheral or pulmonary embolism, MI, hospital admission, exacerbation of heart failure, or death from any cause 14.9/100 patient-years with aspirin 15.7/100 patient-years with warfarin	Significance not assessed