Teaching Clinical Research Methodology by Example has two principal objectives: 1.To tell the story of the research process in action and to provide a glimpse into the minds of the researchers responsible for some of the major advances (and setbacks) in modern medicine. 2. To explain the principles of evidence-based medicine by reviewing the research methods required to prove or disprove a theory. This text is written in a style accessible to health professionals who do not have a background in clinical epidemiology. The first section of the book, ‘Causation’, begins with an explanation of “casual” and “coincidental” associations and follows with examples: * Smoking and lung cancer * Dietary fats and coronary heart disease. * Cause and cure of peptic ulcers. * Viral infection and cancer of the cervix. * Vaccination and autism. * Venous obstruction as the cause of multiple sclerosis. The second section of the book explores prevention, treatment, and the ethical principles of clinical trials. Treatments presented include surgery for breast cancer, acute lymphoblastic leukemia, use of Viagra, stem cells in breast cancer, and the use of aspirin to treat heart attacks. Preventive measures discussed include vaccines, peri-menopausal hormone therapy, aspirin in the treatment of heart attacks, prevention of sudden death after heart attacks, stroke prevention, preventing fatal pulmonary embolism in surgical patients. Written for medical students, practicing physicians in all areas of specialty, medical historians, and medical writers, the book includes a chapter on assessing net clinical benefits of a treatment, and closes with a glossary of methodological terms.