'This handbook is an excellent reflection of the growing maturity and methodological sophistication of the field of Health Technology Assessment. The Handbook covers a spectrum of issues, from primary evidence (clinical trials) through reviews and meta-analysis, to identifying and filling gaps in the evidence. Up-to-date, clearly written, and well-edited, the handbook is a needed addition to any personal or professional library dealing with Health Technology Assessment.' Professor David Banta, TNO Prevention and Health, The Netherlands 'This text presents the most advanced knowledge on methodology in health care research, and will form the backbone of many future studies' - Paula Roberts, Nurse Researcher The 'effectiveness revolution' both in research and clinical practice, has tested available methods for health services research to the extreme. How far can observational methods, routine data and qualitative methods be used in health care evaluation? What cost and outcome measures are appropriate, and how should data be gathered?With the support of over two million pounds from the British Health Technology Assessment Research Programme, the research project for this Handbook has led to both a synthesis of all of the existing knowledge in these areas and an agenda for future debate and research. The chapters and their authors have been selected through a careful process of peer review and provide a coherent and complete approach to the field. The handbook has been a unique collaboration between internationally regarded clinicians, statisticians, epidemiologists, social scientists, health economists and ethicists. It provides the most advanced thinking and the most authoritative resource for a state of the art review of methods of evaluating health care and will be required reading for anyone involved in health services research and management.