Definitions of Epidemiology

The other day my wife, a budding epidemiologist asked me,”can you define epidemiology?”.
I retorted,”why to define something we all know”
She explained the importance of definitions.
Yes, definitions and terminologies are relevant. Those keep the boundaries intact.
I started thinking “is it not at the expense of potential expansion?”.
Do we need to be so rigid?

No definitions are eternal torahs. They are dynamic, it changes to accommodate the extensions of knowledge in the domain.

One interesting image of a big tree extending its branches over the boundary wall flashed before me, and people cutting down those branches mercilessly. My daydream next drifted into someone keep on backtracking with a sword and shield of definitions as the hero of a new knowledge advances forward without caring a damn.

Definitions are not god given. Most can be traced back to a single source ,to an authority or to overarching patriarch or to an author of a blockbuster book.
I am terrible at echoing definitions.
But I tried to parrot the well known aphorism of Last, but failed, cutting a sorry figure before my wife.
I decided to curette out the myriads of definitions of epidemiology down the timeline.

The various definitions are

◆Epidemiology is the study (scientific, systematic, and data-driven) of the distribution (frequency, pattern) and determinants (causes, risk factors) of health-related states and events (not just diseases) in specified populations (neighborhood, school, city, state, country, global). It is also the application of this study to the control of health problems (Source: Principles of Epidemiology, 3rd Edition).

◆“Epidemiology is a method of reasoning about disease that deals with biological inference derived from observations of disease phenomena in population groups” (Lilienfeld)

◆“Epidemiology is the quantitative analysis of the circumstances under which disease processes, including trauma, occur in population groups, factors affecting their incidence, distribution, and the host response and use of this knowledge in prevention and control” (Evans)

◆ “The study of the distribution and determinants of disease frequency in man”(MacMahon and Pugh)

◆ “Science concerned with the occurrence, distribution and determinants of states of health and disease in human groups and populations”.(J.H.Abramson)

◆ Epidemiology is the study of the prevalence and dynamics of stages of health in populations.(Frerichs and Neutra).

◆ “ The science of the mass-phenomenon of infectious diseases or as the natural history of infectious disease, concerned not merely with describing the distribution of disease but equally or more fitting into a consistent philosophy.(Frost)

◆ “The science of the infectious diseases-their prime causes, propagation and prevention”.(Stallybrass)

◆ “The study of disease as a mass phenomenon”.(Greenwood)

◆ “concerned with circumstances…where disease is prone to develop”.(Paul)

◆ “Epidemiology must understand disease ,not so much as it affects invidul or as it behaves under the eye of the observer at any one time or in any one place ,but as it imposes itself on groups of people even if they extend across boundaries set by men for economic,political, and social purposes…”.(Aycock)

◆ “Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problems.”(Last)

To continue………