Epidemiology vs Epidemiological Research

The most centrally relevant, and hence the most important, concept here obviously is that of epidemiology. To me, epidemiology has a singular meaning: it is  (the practice of) community medicine (Miettinen 2011; Miettinen and Karp 2012), although to most teachers of the subject the concept of epidemiology has ‘study’ as its proximate genus. Moreover, the specific difference unique to epidemiology within this genus is commonly said to be the study’s focus on something like ‘distribution and determinants’ of ‘disease’ in populations. I edit those definitions to mean that epidemiology is taken to be a line of research specifically, research on the (rates of) occurrence of phenomena of human health (Miettinen and Karp 2012).

The International Epidemiological Association (IEA) defines epidemiology as ‘the study of the occurrence and distribution of health-related states or events in human populations, including the study of the determinants influencing such states, and the application of this knowledge to control the health problems’ (Porta et al. 2008).

I now distinguish, more sharply than ever before, between epidemiology and epidemiological research; and my concept of the latter now is very different from those above. The concept of epidemiological research naturally is to be deduced from that of epidemiology, whereas epidemiology is defined without any reference to research. In this framework, I define epidemiological research as ‘research any research, however “basic” aimed at advancement of the practice of community medicine’ (Miettinen and Karp 2012).

In these terms, this book is not about teaching epidemiology; it is about teaching epidemiological research. And this book is about only one of the two principal segments of epidemiological research; it is about teaching population level rather than laboratory-based epidemiological research research that addresses the occurrence of illness that is, morbidity (Miettinen 2011) in human populations.

The IEA Dictionary of Epidemiology (Porta et al. 2008) defines morbidity as any departure, subjective or objective, from a state of physiological or psychological well-being. In this sense sickness, illness, and morbid condition are simi￾larly defined and synonymous (but see disease). The WHO Expert Committee on Health Statistics noted in its sixth report (1959) that morbidity could be measured in terms of three units: (1) persons who were ill, (2) the illnesses (periods or spells of illness) that these persons experienced, and (3) the duration (days, weeks, etc.) of these illnesses. In addition, it defines morbidity rate as ‘a term, preferably avoided, used to refer to the incidence rate and sometimes (incorrectly) to the prevalence of disease’.