Antall József szerk.: Orvostörténeti közlemények 55-56. (Budapest, 1970)
TANULMÁNYOK - Mádai Lajos: Semmelweis és a statisztikai tudomány (angol nyelvű közlemény)
proposals, including one by professor Skoda, advising the preparation of a table which would show the connections between deliveries in the streets and the occurances of puerperal fever. According to the proposal that and the other related researches would have been carried out by a professorial commitee in the 1st maternity clinic. The proposition was turned down by the respective ministry on the advice of professor Klein. By professor Klein and others the high mortality caused by puerperal fever was attributed also to the congestion of the 1st maternity clinic. In refuting that allegation Semmelweis used a special statistical method, the analysis of parallel changes. He arranged the data of a long period (first 97 months, then 26 years) in the order of magnitude where the occurence of births was the independent and the mortality rate the dependent variable. By that method he was able to prove that the higher frequency of deaths was not concomitant of the increase in the number of patients, and with the decrease of births the mortality rate did not decrease but increased. Thus he clearly demonstrated that there was no casual connection betv/een overcrowded wards and high mortality. Table 5 Maternal mortality in January and July, selected years, in the 1st maternity clinic of Vienna* January July Year Mortality Year Mortality Year Deliveries number number percentage Year Deliveries number number percentage 1842 307 64 20.84 1842 231 48 20.78 1843 272 52 19.11 1846 252 33 13.10 1844 244 37 15.16 1841 190 16 8.42 1841 254 37 14.56 1845 245 15 6.12 1846 336 45 13.39 1844 206 9 4.37 1845 303 23 7.59 1847 250 3 1.20 1848 283 10 3.53 1843 191 1 0.52 1847 311 10 3.21 1848 269 1 0.37 1849 403 9 2.23 — — —— By correlating the data of the above table I checked the correctness of Semmelweis's conclusions and found that there was no connection between the number of births and the mortality rate (r -—0.371), The above method of parallel changes already contained the essence of correlation calculation, the measuring of causal connections. Even the simple mathematical formula used by Semmelweis was suitable for analysing the cause and effect relations of the problem investigated. It was Galton who first made use of modern correlation calculation in his researches on genetics in 1888, we! 1 after the death of Semmelweis (12), * Semmelweis l.c.p. 254 — 255. XLV. Táblázat.
