By the end of the 19th century, the emphasis of medicine was beginning to shift. No longer did research concentrate on the infectious diseases that had once spread through continents. Instead, scientists were more concerned with chronic degenerative disorders.

Advances in general scientific understanding, and in the technology available, helped the investigation of disease: the workings of the endocrine system were unravelled, for example, and insulin discovered; radiation was hamessed, and X-rays used for diagnosis; electron microscopes, ECGs and EEGs, allowed the body to be probed in detail as never before.

N. Duin and J. SutcliffeA history of medicine: from prehistory to the year 2020. Internet: <storage.googleapis.com> (adapted).