Epidemiology: Principles & Methods, by Brian MacMahon and Dimitrios Trichopoulos
Admittedly, epidemiology is a rather dry subject that most people would not find it very interesting to read about. Fortunately, or unfortunately perhaps, I am not most people, and one of my characteristic responses in a period of health crisis such as our own time is to ponder and study the sort of field that deals with precisely these matters. While the material discussed in this book is rather dry because epidemiology is a highly historical and statistical field full of categories and the categorization and exploitation of data, some of which is not particularly available for huge swaths of human populations or huge spans of human history, these matters provide a great deal of interest to those who are able to look beyond the material that is covered itself to think and reflect upon the importance and context of this information and its reliability as well as its profound limitations when it comes to being able to address current events. And even if this book is admittedly a bit tough to get through if one is not fond of statistical analysis as much as I am, there are still reasons why one should know at least something about the methods and principles of epidemiology, not least because of the way that at least some people and institutions would seek to exploit the approach of this field for political purposes, which is always worth knowing.
This book is about 300 pages of core material divided into ten chapters. After a preface and acknowledgements, the authors begin by defining epidemiology and looking at its history and aims (1). After that the book discusses the question of cause and matters of association (2) as well as a discussion of the grouping of ill people and the classification of disease (3). Another chapter then follows on measures of disease frequency within populations (4) and then the strategies and ways of formulating and testing hypotheses (5) to help counteract a given disease. The next three chapters all look at various ways in which diseases and their effects on population may be understood, namely through the dimensions of time (6), place (7), and person (8), where data about rates, local, regional, and international clusters of diseases, and the impact of demographics on disease can be important in understanding risk factors and figuring out strategies against illness. Finally, the book ends with a discussion of two sorts of studies in the field, namely cohort studies (9) and case-control studies (10), after which the book ends with references and an index.
In the broadest and most general terms, epidemiology is a field that works best with large amounts of data (some of which may be admittedly private and somewhat intrusive to gain access to) as well as with the benefit of hindsight. For example, it was determined after the fact that cervical cancer resulted from a sexually transmitted disease in large part because of the stark lack of transmission among a population of not sexually active people (namely nuns). That this realization has not yet led to sensible restraint on sexual conduct but rather attempts to coerce small children to be inflicted with a dangerous vaccine is demonstration of the way that epidemiological knowledge does not lead straightforwardly to sound or moral policy. Likewise, the authors point out that moderate drinking of one to three drinks daily reduces the risk of heart attacks and strokes, but uses this insight as a way of mocking neo-prohibitionists rather than giving credit to the Bible’s moderationist perspective. Likewise, the historical and retrospective aspects of epidemiology should lead those who depend on this field to approach their studies with a sense of humility, but that does not appear to be the case from this book or from the contemporary behavior of those who are involved in the field.