This is a practical guide to the design, conduct, analysis and interpretation of epidemiological studies. The clear and concise text is supplemented throughout by appropriate illustrative examples and helpful practical hints, all designed to support and encourage newcomers to the field. The book assumes no prior knowledge. Sufficient material is provided to enable the reader to undertake soundly based studies which take account of the most recent advances in epidemiological concepts and methods. The book also includes sections on ethical issues and how they should be addressed, and costing a study. It aims to make epidemiological method accessible to a broad range of individuals, including hospital clinicians, general practitioners and public health physicians and it will serve as an excellent introductory text for those training in epidemiology and public health.