The Epidemiology section examines epidemiology as the basic science of preventive medicine and public health-with information on human ecology, infectious disease epidemiology, disease outbreak investigation, chronic disease epidemiology, clinical epidemiology, methods for evaluating clinical tests, and methods for improving clinical decisions. The Biostatistics section covers the major biostatistical concepts and methods used in medical research. It also addresses special topics such as random allocation, sample size determination, use of life table methods, elementary applied probability analysis, decision analysis, and the use of nonparametric tests for ordinal data. The Preventive Medicine and Public Health section examines the options available to physicians and communities for promoting health and preventing disease. After it discusses the rotes of local, state, and federal governments in promoting health, it outlines the US health promotion and disease prevention goals for the year 2010. It concludes with a look at the current strengths and weaknesses of the US medical tare system and a cost analysis of the economics of prevention.