Scientific revolution and the clinico-pathological paradigm In this edition of Population Health Metrics, a series of papers describes new, automated methods for analyzing verbal autopsy questionnaires. Are we witnessing a revolution in the computer-based analysis of verbal autopsies? The use of the word, revolution, brings to mind Thomas Kuhn’s seminal essay, The Structure of Scientific Revolutions, first published in 1962, and his concept of the scientific paradigm [1]. Verbal autopsies, as we now know them, are not a new concept, but rather are late developments within the clinico-pathological paradigm that displaced the humoral theory of disease in the late 18 and early 19 centuries. We could mark the beginnings of this scientific revolution from the publication in 1761 of Morgagni’s The Seats and Causes of Disease Investigated by Anatomy [2]. Encyclopedic in scope, it is over 2,000 pages in length in its English translation. His general plan is to present symptom histories of patients who had died, describe the findings at autopsy, speculate on the likely causal relationships between pathology and symptoms, and finally to discuss similar cases found in a literature extending back from recent centuries to the ancients. The first level of classification is by the three major body cavities (head, thorax, and belly [sic]) and surgery; the second level is by symptom group. At the end of the three volumes are his indices, which he regarded as critical: one of these lists symptoms alphabetically, cross-referencing them to the pathology of disease case-by-case; another lists pathological lesions, similarly cross-referencing them to symptom histories. His underlying thesis, that clinical symptoms reflect organ dysfunction, was not to be fully accepted for over half a century. This thesis can be briefly stated, but it is the sheer weight of evidence, somewhat in the manner of The Origin of Species, that makes his case. That was not his only purpose: he wanted this to be a working manual (albeit a very large one) for physicians and anatomists. Equally, we could mark the endpoint of this scientific revolution with the publication in 1819 of another massive work Laennec’s A Treatise on Diseases of the Chest [3]. Laennec argued that the symptom history was inaccurate. Using his new invention, the stethoscope, he linked detailed auscultatory findings to autopsy findings of pulmonary pathology. All of modern medicine rests upon this linkage. Morgagni validated pathological anatomy as the cause of disease by using the symptom history as his gold standard. Sixty years later, Laennec dismissed the symptom history as inaccurate and validated auscultation using pathological anatomy as his gold standard. In the course of this paradigm shift, pathology had been moved from the margins of the medical solar system to its heart. In Foucault’s words, “The space of configuration of the disease” was now superimposed “upon the space of the localization of illness.” [4] Medical practice in the 18 century had depended heavily on what we would now call unstructured symptom histories. Physical examination was limited in the main to the observation of the fully clothed patient and palpation of the pulse. Laennec’s work led to a wave of enthusiasm for auscultation to the exclusion of other methods of diagnosis. In attempting to restore balance, Pierre Louis “initiated a method of clinical teaching based on precise observation and statistical analysis.” He began the structuring of the clinical history by introducing direct questioning. In the words of Stanley Reiser [5]: