On Being an Epidemiologist.

This commentary addresses being an epidemiologist at a time when the field of epidemiology again faces a paradigm shift as the tools for research on human health draw increasingly on emerging technologies-various omics and new methods for collecting individual data at high intensity-and on new methods for carrying out research through administrative and health care data bases linked to biobanks. At the same time, epidemiologists in public health practice continue to face the usual array of challenges, but with the threat of global issues as well. The profession of epidemiologist is not monolithic; it embraces a broad range of activities and professional venues, reflecting the many contexts where epidemiologists do their work, the nature of the problems addressed, and the span and application of their findings. Obtaining data from people and populations comes with serious ethical obligations related to privacy and confidentiality of individuals and respect for the populations studied. Beyond generating and analyzing data, epidemiologists engage in guiding action through the evidence they have created with the ultimate goal of advancing health. This commentary addresses "mega-trends" that will affect the profession in the decades to come.