Can pooled numbers judge an operation? The 1835 report on Civiale's statistics

Positions

1. Civiale: the numbers favour crushing

   Civiale collected the results of thousands of lithotomies reported by surgeons across Europe and set them against his own lithotrity series, arguing that the difference in deaths showed crushing to be safer.

   Sources

   1. H. W. Herr, Civiale, stones and statistics: the dawn of evidence-based medicine, BJU Int 2009;104(3):300-302 Secondary
   2. James Lind Library: Poisson, Dulong, Larrey et Double 1835 Museum or society

2. The commission: large numbers matter, but these are not comparable

   Poisson, Dulong, Larrey and Double accepted that large numbers have value. They found Civiale's lithotomy figures unfit to fix the mortality of cutting with any accuracy: the series were retrospective, drawn from many surgeons, selected in unknown ways and judged by unknown criteria. They urged him to gather more cases with fuller detail.

   Sources

   1. English translation of the 1835 Académie report, Int J Epidemiol 2001;30(6):1246-1249 Primary
   2. James Lind Library: Poisson, Dulong, Larrey et Double 1835 Museum or society
   3. Poisson, Dulong, Larrey et Double, Recherches de statistique sur l'affection calculeuse, par M. le docteur Civiale. Comptes rendus hebdomadaires des séances de l'Académie des sciences 1835;1:167-177 Primary

3. Double: counting does not belong in medicine

   The physician on the commission rejected the numerical method in principle. As Tröhler translates him, statistics require forgetting that a patient is an individual and treating him as a fraction of the species, and the certainty of mathematics, proper to astronomy, should not be sought in medicine.

   Sources

   1. Tröhler 2020, J R Soc Med 113(9):360-366 Secondary

4. Poisson: the objection fails

   The probabilist rejected Double's objection, and in 1837 published on the law of large numbers.

   Sources

   1. Tröhler 2020, J R Soc Med 113(9):360-366 Secondary

5. Risueño d'Amador (1837): large numbers cannot judge the art

   When the argument moved to the Académie de médecine in 1837, over Pierre Louis's numerical method, Risueño d'Amador held that no doctor could judge the usefulness of his art from large numbers and that the method would reduce medicine to mechanical routine and chance.

   Sources

   1. Tröhler 2020, J R Soc Med 113(9):360-366 Secondary

Evidence

The report itself (Comptes rendus 1835) is known to the kit through the James Lind Library record and a 2001 English translation; the French original was not retrieved. Double's and Risueño d'Amador's words are known through Tröhler's modern translation, so they are paraphrased here. Herr (2009) gives the figures Civiale compiled. Every version of those figures shows roughly one death in five after cutting against one in forty to fifty after crushing, but the commission's point was that the two series could not be fairly compared.

Current standing

The commission's objections (non-comparable groups, unknown selection, retrospective reports, unstated outcome criteria) are the standard objections to observational comparisons of treatments. The dossier notes that clinical judgement over numbers dominated French medicine through the 1830s and 1840s, and that statistical comparison won general acceptance only in the twentieth century, with randomised trials from the late 1940s. The film closes the scene by saying that the quarrel between the average and the individual is not over.

All sources