TY - JOUR T1 - A prediction rule identified patients with atrial fibrillation at low risk of stroke while taking aspirin JF - Evidence Based Medicine JO - Evid Based Med SP - 29 LP - 29 DO - 10.1136/ebm.9.1.29 VL - 9 IS - 1 A2 - , Y1 - 2004/01/01 UR - http://ebm.bmj.com/content/9/1/29.abstract N2 - van Walraven C, Hart RG, Wells GA, et al. A clinical prediction rule to identify patients with atrial fibrillation and a low risk for stroke while taking aspirin. Arch Intern Med 2003;163:936–43.OpenUrlCrossRefPubMedWeb of Science 
 
 Q What is the accuracy of an age independent clinical prediction rule for identifying patients with non-valvular atrial fibrillation (AF) who are at low risk of all cause stroke or transient ischaemic attack (TIA) while taking aspirin? Clinical impact ratings GP/FP/Primary care ★★★★★★☆ IM/Ambulatory ★★★★★★☆ Geriatrics ★★★★★★☆ Cardiology ★★★★★★☆ Design: analysis of data from 6 randomised controlled trials (RCTs) to derive and validate a clinical prediction rule. Setting: US, Canada, Denmark, and the Netherlands. Patients: 2501 patients (mean age 70 y, 67% men, 93% white) with non-valvular AF who were participating in 1 of 6 RCTs. All patients had had no stroke or TIA for at least 6–24 months before entering in the trials and received aspirin at dosages between 75–325 mg/day. In most studies, patients were excluded if they had clinical indications for or contraindications to oral anticoagulation or aspirin therapy, or if they had a recent acute coronary syndrome or cardiac revascularisation. Patients were randomly … ER -