title: Immortal person-time bias in observational studies in cardiac surgery.
authors.forename: Muthiah
authors.initials: M
authors.lastname: Vaduganathan
authors.forename: Samy
authors.initials: S
authors.lastname: Suissa
mesh_terms: D001241:Aspirin / Q000009:adverse effects / Q000627:therapeutic use*; D015982:Bias; D000077144:Clopidogrel; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000401:mortality; D003627:Data Interpretation, Statistical; D004359:Drug Therapy, Combination; D006470:Hemorrhage / Q000139:chemically induced; D017052:Hospital Mortality; D006801:Humans; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D011183:Postoperative Complications / Q000401:mortality / Q000517:prevention & control*; D012107:Research Design; D018570:Risk Assessment; D012307:Risk Factors; D013988:Ticlopidine / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin