Now in its Fourth Edition, this best-selling text presents a step-by-step approach to critical and efficient reading of the health research literature. Health care professionals will learn how to evaluate clinical studies, identify flaws in study design, understand the significance of statistics, and apply the evidence from clinical research in practice. A new section in this edition -- Considering Costs and Evaluating Effectiveness -- offers guidance in reading articles on decision analysis and cost-effectiveness analysis. Throughout the text are unique learning aids such as checklists of questions to ask, scenarios illustrating study design errors, flaw-catching exercises, and flowcharts for assessing statistical methods.