Public Health and Nephrology: Contributions of Epidemiology to the Study, Understanding, Prevention and Treatment of Kidney Disease.

Kidney disease is frequently described as a public health problem. This chapter will unpack what we mean by "public health" and by "taking a public health approach." We will consider the global burden of kidney diseases and their determinants, with a focus on chronic kidney disease. We will explore the aetiology of chronic kidney disease across the life course and the way in which kidney health frequently reflects inequities in societal health, therefore requiring a public health response. We will describe some of the public health endeavours that help address these problems and then introduce epidemiology as the core science of public health. We will describe the common epidemiological study designs with a focus on observational studies and explore the role of the various study designs in addressing different types of research question, and thereby contributing to distinct aspects of disease understanding. We will introduce concepts of primary and secondary prevention and explore the ways in which the application of different epidemiological study designs has contributed to the knowledge and understanding of kidney diseases. We will discuss the strengths and weaknesses of different study designs and explain how epidemiological methods allow for the quantification of public health problems.