Eligibility of Studies
Inclusion criteria for retrieved studies were: (a) randomised controlled phase II or III trials of VKAs, ASA, clopidogrel and novel oral anticoagulants in patients with non-valvular AF; (b) randomised treatment allocation, (c) intention-to-treat analysis and (d) follow-up more than 1 year. In order to reflect current practice patterns, we excluded studies or study arms where VKAs were administered at non-standard doses (eg, low fixed doses) or antiplatelet agents other than ASA or clopidogrel were tested.
Data Abstraction and Quality Assessment
Two independent reviewers (AD, EP) performed data abstraction. We used consensus to resolve discrepancies. The endpoints of primary interest were: stroke, composite of ischaemic stroke or systemic embolism, death from any cause, and major bleeding. Definitions of endpoints were the same across all trials, with the exception of major bleeding where we used the trial-specific definition. We used data from the intention-to-treat populations, unless otherwise specified.