The relationship between the rise of modern medicine and the incidence of disease is controversial. It might be expected that the greater a society's investment in medical research and health care, the less disease there would occur. But while it is possible to target certain problems for solution, a multiplicity of factors produce overall improvements in health, and it must be appreciated that medicine, disease and society are not constant and uniform categories. The history of medicine shows that relations between medical practitioners, medical institutions, patients' expectations and diseases have been constantly changing. Calculating the costs of medical services, and the extent of sickness in past societies are immensely complex tasks. Another way of perceiving the relationship between the advent of modern scientific medical services and disease is to see not so much a diminishing quantity of disease, but a change in the quality – i.e. in the types and virulence – of diseases. Demographers often refer to an ‘ epidemiological transition ’ from pre-industrial patterns of epidemic infectious diseases to a modern pattern of deaths from chronic degenerative diseases. This raises the question whether morbidity and mortality patterns have fundamentally differed before and after industrialization, or whether only changes in perceptions and managing diseases have taken place.

Coupled with the rapid and substantial decline in infant mortality, the increased registered incidence of heart disease and cancers (the ills of middle and old age) has been an outstanding feature of industrial societies during the twentieth century.