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Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship—Observational Studies

Published online by Cambridge University Press:  20 June 2016

Graham M. Snyder*
Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts
Heather Young
Denver Health Medical Center, University of Colorado Hospital, Denver, Colorado
Meera Varman
Creighton University School of Medicine, Omaha, Nebraska
Aaron M. Milstone
Johns Hopkins Medical Institutions, Baltimore, Maryland
Anthony D. Harris
University of Maryland School of Medicine, Veterans Affairs Maryland Health Care System, Baltimore, Maryland
Silvia Munoz-Price
Institute for Health and Society and Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin
Address correspondence to Graham Snyder, Mailstop SL-435, 330 Brookline Ave, Boston, MA 02215 (


Observational studies compare outcomes among subjects with and without an exposure of interest, without intervention from study investigators. Observational studies can be designed as a prospective or retrospective cohort study or as a case-control study. In healthcare epidemiology, these observational studies often take advantage of existing healthcare databases, making them more cost-effective than clinical trials and allowing analyses of rare outcomes. This paper addresses the importance of selecting a well-defined study population, highlights key considerations for study design, and offers potential solutions including biostatistical tools that are applicable to observational study designs.

Infect Control Hosp Epidemiol 2016;1–6

SHEA White Papers
© 2016 by The Society for Healthcare Epidemiology of America. All rights reserved 

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