Anticoagulant given^preoperative:Prid:Pt:^Patient:Nom
anticoagulant given^preoperative:prid:pt:^patient:nom
Anticoagulant given^preoperative:Presence or Identity:To identify measures at a point in time:^Patient:Nominal
anticoagulant given^preoperative:presence or identity:to identify measures at a point in time:^patient:nominal