1959 - 60 years and still all to do ...
'Computers' have not always been a matter of mechanism. Depending on your definition, what we describe as medical informatics, clinical informatics and nursing informatics could be said to originate in the data-gathering, recording and graphic work of John Bell, Florence Nightingale and many other pioneers. If John Bell and Florence Nightingale introduced the arrival of modern public health and nursing respectively, there is still a need to 'fix' the history of medical informatics.
"Pinpointing the beginning of the field of medical informatics is challenging, but it is perhaps best to begin any discussion of the field with the 1959 paper “Reasoning foundations of medical diagnosis; symbolic logic, probability, and value theory aid our understanding of how physicians reason” by Ledley and Lusted [19]. Ledley went on to invent the whole-body CT scanner [20], and Lusted became a leader in the field of medical decision-making. Their 1959 paper, however, laid out a probabilistic model for medical diagnosis, with grounds in set-theory and Bayesian inference." p.642.
[19] R.S. Ledley, L.B. Lusted, Reasoning foundations of medical diagnosis; symbolic logic, probability, and value theory aid our understanding of how physicians reason, Science 130 (3366) (1959) 9–21.
[20] D.F. Sittig, J.S. Ash, R.S. Ledley, The story behind the development of the first whole-body computerized tomography scanner as told by Robert S. Ledley, J. Am. Med. Inform. Assoc. 13 (5) (2006) 465–469.
Wright, A., Sittig, D.F. (2008) A four-phase model of the evolution of clinical decision support architectures, International Journal of Medical Informatics. 77: 641–649.