An Analysis of Nineteenth-Century Literal Causes of Death from the Age of Miasmas to Germ Theory

Historical mortality analysis is often confounded by changing disease environments, diagnostic criteria, and terminology. Recorded causes of death are shaped by these local and historical contexts. We analyze changing literal causes of death during the shift from miasmatic to germ theories of disease using death records from two Massachusetts towns for selected years spanning 1850 to 1912. This analysis demonstrates that (1) International Classification of Diseases (ICD) classifications are more stable, yet potentially less informative, than the literal causes recorded in death accounts, (2) recorded causes of death often include additional qualifications and elaborations beyond basic literal causes of death, and the use of such qualifiers rose dramatically during the late nineteenth century, (3) social biases are clearly evident in the extent to which causes of death were further described or qualified, and (4) the additional descriptive qualification of deaths during this period of often ambiguous historical causes of death can potentially aid in efforts to classify causes of death and derive robust estimates of cause-specific mortality trends.