32 
Multiple Cases of Disease in the Same House 
to the 38th Annual Report of the Registrar-General for Ireland. On p. 34 we 
find that in the ten years 1876-1885 inclusive there were 12 multiple cancer 
houses in the City of Dublin. In all these instances in only one house did the two 
deaths occur in members of the same family. There are no cases — or at least no 
cases recorded — of more than two deaths in the same house. 
Unfortunately the paper does not give either (i) the number of inhabited 
houses in the City of Dublin during the ten years under consideration, or (ii) the 
total number of deaths in the City of Dublin from cancer. What useful purpose 
the then Registrar-General could conceive such data would serve completely puzzles 
me*. He draws up a summary of his Tables, introducing it with the words: 
" I venture to draw attention to some of the main facts which they disclose," and 
clause (7) runs : 
" That in some instances more than one case of cancer has occurred amongst different 
families living in the same house, or amongst successive occupants of the same house." 
Now unless this is meant to be interpreted as a suggestion that the multiple 
houses are in excess, it must be anticipated from the mere random occurrence of 
cancer. Anyhow without further information the data on this point, as on many 
others in this Special Report on Cancer in Ireland, are wholly worthless and the 
publication does no credit to a Government Department. 
I have striven to obtain the requisite additional data from the present 
Registrar-General for Ireland. He most kindly informs me that the inhabited 
houses of the City of Dublin numbered 23,896 in 1871 and 24,211 in 1881; and 
for the Registration Area of Dublin, 34,118 in 1871 and 36,232 in 1881. All 
these data are from the Censuses of those years. The deaths from cancer in the 
Registration Area for 1876 to 1885 inclusive were 1714, but how many of these 
occurred in the City of Dublin he is not able to tell me. I presume the late 
Registrar-General must have known these deaths in order to detect multiple 
houses, but apparently they cannot now be ascertained. It is clear therefore that 
the data of the " Special Report on Cancer " must remain practically worthless. 
If we suppose the City of Dublin to have had a number of cancer cases 
proportionate to its houses we might take : 
n n-, h(23,896 + 24,211)-,.-. n „ 
Cancer Cases in City = f , 0 ,' „ Krhi^i 1714 = 117 2, 
J ^ (34,1 IS + 36,232) 
roughly § of the cases in the Registration Area. 
Since the middle of our period is not very far from the Census year 1881, we 
might take 
« = 1172, m = 24,211. 
* Cancer in the Eeport is associated with alcohol, syphilis, smoking, etc., in an equally unscientific 
manner. Unless we know the incidence of each character or disease in the population, how is it possible 
to determine whether the association is merely due to chance or not ? 
