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It has been almost a quarter century since the first edition of Medical Epidemiology was written. That original text was developed out of the experience of teaching epidemiology to medical students at Emory University and the University of Cincinnati. Our goal was to present the field of epidemiology in an approachable manner, emphasizing how these methods can advance medical knowledge.
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At the time, we could not have anticipated how widely the book would be used and read. Translation into multiple different languages has made Medical Epidemiology accessible to an international audience, and the publishers have been generous in their support of four subsequent editions to keep its contents current. Each successive edition provided an opportunity to revisit the examples that were used in a field that was evolving rapidly.
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It has been a decade since the last iteration of this book appeared, and in the interim there have been transformative changes in the way epidemiologic methods are being used in health care. Some of these changes have been spurred on by the widespread adoption of electronic medical records, making clinical information much more accessible for research purposes. Also, the promotion of clinical and translational research by the National Institutes of Health has given additional focus to moving discoveries from the laboratory bench to the patient's bedside and ultimately to the community at large. Even as translational work has advanced, there has been a paucity of educational material to help prepare investigators for research careers in this area.
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Major shifts also have occurred at the policy level, with a growing recognition that the quality of health care is uneven, that advances in medical knowledge often are slowly translated into clinical practice, and that many widely used treatments are poorly justified on the basis of patient-centered outcomes research. As increasing attention is being paid to reimbursement based on the quality and value of care, it will become incumbent upon practitioners to be able to interpret and use research on comparative effectiveness and quality improvement.
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With all of these changes underway, we concluded that a fundamental rethinking was required about the contents of Medical Epidemiology. As a consequence, this book has been rewritten in its entirety. In addition, new chapters have been added on many topics, including global health, social determinants of health, health inequalities, comparative effectiveness, quality of care, variations in care, and implementation science. We are not aware of any other existing book with such a broad range of topics, and we hope that the current work fills a void for students, as well as practitioners.
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With such a broad range of topics, it was necessary to assemble a truly interdisciplinary team of authors. Gone are the days when a group of epidemiologists could write a textbook in isolation from investigators in other fields. In addition to our core epidemiologic expertise, the writing team for this book included, among others, experts in medical sociology, internal medicine, psychiatry, global health, health disparities, health economics, health services research, biostatistics, population sciences, community-based participatory research, database design, and translational science. If ever it took a village to write a book, this is a prime example.
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We realize full well that with this breadth of material, some compromises had to be made in the level of detail provided. Accordingly, we view this book as a primer, and readers who wish to explore specific topics in greater depth are encouraged to pursue the cited work under Further Reading at the end of each chapter.
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We have tried to keep this book grounded in medical care by introducing each chapter with a Health Scenario. We also encourage readers to assess their knowledge acquisition through Study Questions at the end of each chapter. Although any textbook on epidemiology is obliged to cover essential quantitative topics, we have attempted to keep this book accessible to a wide readership by limiting the methodological discussions to the most essential material. For those who are interested in more detail on the calculation of various epidemiologic measures, free, user-friendly resources are available, such as the Centers for Disease Control and Prevention's Epi Info (http://www.cdc.gov/epiinfo/).
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Hopefully, this book will be a faithful heir to its four predecessors. At the same time, we have tried to expand on the original mission by highlighting the ways in which epidemiology can advance and be advanced by its sister sciences. There was never a time of greater need for appreciating how epidemiology can improve both the delivery of medical care and the health of populations. In some small measure, we hope that this book begins to fill that need.
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Raymond S. Greenberg, MD, PhD
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