Like'the previous versions, the fifth edition of An Introduction to Research in the Health Sciences has two overall aims. 1) To introduce the fundamental principles of research methodology and explain how these principles are applied for conducting research in the health sciences. 2) To demonstrate how evidence produced through research is applied to solving problems in everday health care. This book is written in an accessible style. It maintains the traditions of the previous editions, with examples, questions, feedback sections, and an extensive glossary.