The purpose of this book is to provide a collection of public health research methodologies in one volume covering both quantitative and qualitative research together with evaluation, case studies, analysis of existing data, experimental and documentary research. Epidemiological research is given a special focus in this book. A number of research methodologies exist for public health research, and this book endeavours to provide details for each methodology. The fundamental principal throughout is to simplify the methodologies and make it easy and practical for researchers (both junior and more experienced) to use them in their investigations.