One effect of rising health care costs has been to raise the profile of studies that evaluate care and create a systematic evidence base for therapies and, by extension, for health policies. All clinical trials and evaluative studies require instruments to monitor the outcomes of care in terms of quality of life, disability, pain, mental health, or general well-being. Many measurement tools have been developed, and choosing among them is difficult. This book provides comparative reviews of the quality of leading health measurement instruments and a technical and historical introduction to the field of health measurement, and discusses future directions in the field. This edition reviews over 100 scales, presented in chapters covering physical disability, psychological well-being, anxiety, depression, mental status testing, social health, pain measurement, and quality of life. An introductory chapter describes the theoretical and methodological development of health measures, while a final chapter reviews the current status of the field, indicating areas in which further development is required. Each chapter includes a tabular comparison of the quality of the instruments reviewed, followed by a detailed description of each instrument, covering its purpose and conceptual basis, its reliability and validity, alternative versions and, where possible, a copy of the scale itself. To ensure accuracy, each review has been approved by the original author of each instrument or by an acknowledged expert.