This book is a pivotal textbook for those considering, undertaking or appraising an evidence synthesis based on IPD for clinical research, especially those interested in intervention effects, modifiers of treatment response, identification of risk or prognostic factors, and the development and validation of risk prediction models. It covers all the key concepts and stages of a systematic review and meta-analysis of IPD, focusing primarily on the synthesis of randomised trials, as well as specialist topics, such as risk prediction, observational studies and advanced statistical methods. The book offers non-technical and practical examples, summary and learning points, and guidance including reporting criteria, software demonstrations, and illustrated applications. Describing the key features of the approach, this book will enable the reader to: * Understand when the IPD approach is needed * How to undertake the systematic review and identify relevant evidence * How to obtain, check and manage the IPD * How to minimise potential biases and clearly report methods and results * How to make the best use of IPD meta-analyses to inform policy, practice and research. Case-study chapters are also provided, where the trials and tribulations of undertaking IPD projects of randomised trials and observational studies are described by researchers in a range of clinical fields.