184 BIOLOGY OF DEATH 



people the Dutch in some investigations carried out 

 by Dr. F. S. Cram of the Prudential Life Insurance Com- 

 pany, with the assistance of the distinguished mathe- 

 matical statistician, Mr. Arne Fisher. 



The Dutch Government publishes annually data which 

 undoubtedly furnish the best available material now exist- 

 ing in the world for the purpose of determining whether 

 or not there is a positive or negative correlation between 

 infant mortality and the mortality in the immediately 

 subsequent years of life. Fisher's mathematical analy- 

 sis embraces a very large body of material, including 

 nearly a million and a half births, and nearly a quarter 

 of a million deaths of males occurring in the first five 

 years of life. The Holland data make it possible to 

 develop life tables for every cohort of births and this 

 has been done in the 16 cohorts of males during the years 

 1901-1916. The data also make it possible to work up 

 these life tables for urban areas and for rural areas. 

 After carefully eliminating secular disturbances the 

 Holland material appears to prove quite conclusively for 

 the rural districts that there is a definite negative corre- 

 lation, of significant magnitude, between infant mortality 

 and the mortality in the immediately subsequent years of 

 life. The only place where positive correlation appears is 

 in the four large cities of the country with more than a 

 hundred thousand inhabitants each. Fisher makes the 

 following point (in a letter to the present writer) in ex- 

 planation of these positive correlations. He says : 



The larger cities are better equipped with hospital and clinical 

 facilities than the smaller cities and the rural districts. More money 

 is also spent on child welfare. Is it therefore not possible that many feeble 

 lives who in the course of natural circumstances would have died in the 

 first year of life are carried over into the second year of life by means 

 of medical skill? But medicine cannot always surpass nature, and it 



