No. 630] HUMAN MORTALITY RATES . 15 



with the respiratory system. It is apparent, of course, 

 that the matter of the placing of diphtheria can be argued 

 from both sides, but on the whole I incline to the view 

 that it belongs here with the respiratory organs rather 

 than with the blood. 



Item 10, "Influenza," is so obviously respiratory as to 

 require no discussion. The same may be said of item 8, 

 "Whooping cough. " 



The reason for including item 6, "Measles," here is 

 clearly stated by Spengarn 9 when he says regarding 

 measles: "The mortality of this disease is largely due to 

 the pulmonary complications," and further: "The high 

 mortality among the measles patients in children's hos- 

 pitals is attributed to bronchopneumonia." 



Table II brings out very clearly one important point in 

 favor of the present classification. It is evident from an 

 examination of the four columns of rates that the usages 

 in respect of the diagnostic terminology of respiratory 

 affection, especially the pneumonias and bronchitis, differ 

 greatly in these three countries. Yet the totals for all 

 respiratory system deaths are closely similar for all 

 three countries and periods. In other words, the organ- 

 ological totals get rid to a large degree of one of the 

 greatest sources of error in vital statistics, the varying 

 terminology of disease in different regions. 



The first and the fourth items in Table III present a 

 new angle of the problem of the classification of the 

 causes of death which needs particular discussion. These 

 items, "Premature birth" and "Injuries at birth" repre- 

 sent a part of the items 151 and 152 of the International 

 Classification. In the International Classification, item 

 151, which comes under the general heading "XI. Early 

 infancy," has this general title "Congenital debility, 

 icterus and sclerema (total)." This contains two sepa- 

 rate subdivisions not numbered, the first being "Pre- 

 mature birth," and the second "Congenital debility, 



» Spengarn, A., article "Measles" in Ref. Handbook Med. Sci., Vol. VI, 

 p. 283, 1916. 



