Koch's main contribution to the principles of evidence-based medicine (EBM) was the formulation of his four postulates which helped to confirm the causal relationship between pathogenic microbes and infectious diseases, and in enabling credible diagnosis of such diseases through microscopy, inoculation and cultivation. A further stage in the development of EBM is represented by the Bradford Hill criteria, a group of nine principles applicable to non-transmissible diseases.
The present discussion focuses on the limitations of EBM and its primary significance and use.