This book is a general reference designed for individuals from a broad range of professional backgrounds at various stages of learning about medical information systems: those training for careers in informatics, those actively conducting evaluation studies, and those responsible for information systems in medical centers. It attempts to explain why medical information resources should be studied, and why this is a challenging process. It explores the options for conducting such studies, and specifically deciding what topic to study. It also explains how to design, carry out, and/interpret a study using a particular set of techniques, how to conduct studies in the context of health care organizations, and how to communicate study designs and study results to the proper audience.