The fifth edition of "A Dictionary of Epidemiology," edited by Miquel Porta and sponsored by the International Epidemiological Association (IEA), is a comprehensive and updated reference. This revised version, following John Last's work, includes numerous new terms, illustrations, and a fresh design. It covers both common and advanced epidemiological terms, as well as recent methodological innovations. The dictionary expands its scope to include epidemiological methods in clinical research, public health practice, genetics, and social sciences. New terms from biostatistics, clinical epidemiology, environment, sociology, and life cycle epidemiology are included, along with genetic and molecular epidemiology, health promotion, preventive medicine, health economics, and bioethics. This dictionary is a valuable resource for professionals in clinical medicine, public health, and other health and social sciences, providing clarity on epidemiological and methodological definitions related to human health.The fifth edition of "A Dictionary of Epidemiology," edited by Miquel Porta and sponsored by the International Epidemiological Association (IEA), is a comprehensive and updated reference. This revised version, following John Last's work, includes numerous new terms, illustrations, and a fresh design. It covers both common and advanced epidemiological terms, as well as recent methodological innovations. The dictionary expands its scope to include epidemiological methods in clinical research, public health practice, genetics, and social sciences. New terms from biostatistics, clinical epidemiology, environment, sociology, and life cycle epidemiology are included, along with genetic and molecular epidemiology, health promotion, preventive medicine, health economics, and bioethics. This dictionary is a valuable resource for professionals in clinical medicine, public health, and other health and social sciences, providing clarity on epidemiological and methodological definitions related to human health.