Using restriction to minimize bias in observational studies.
Mintu P
MP
Turakhia
Paul A
PA
Heidenreich
D001281:Atrial Fibrillation / Q000628:therapy; D015982:Bias; D057186:Comparative Effectiveness Research; D006801:Humans; D019370:Observation; D015588:Observer Variation; D011787:Quality of Health Care; D016896:Treatment Outcome