368 Statistical Stmhj of Anti-T uphold Inoctdatioii 
TABLE III. 11th Lancers in India*. 
Inoculation 
+ 
Not attacked 
148 
481 
629 
Attacked 
2 
58 
60 
Totals 
150 
539 
689 
A= --780018, ^■ = l-358832, 
- ■0109r''- -12184^- ■055239r3- ■529956rH>'- '34425 = 0, 
r= -4802 ±-0593. 
The absence in Pretoria of Mr Maynard does not permit me to ascertain from liim the source 
of the total for uninoculated. In Lieutenant Luxmore's Report, Journal of Royal Army Medical Corps, 
Vol. VIII. p. 492, the strength of the regiment is given as 593 including 84 women and children. Of the 
five officers' wives, three were inoculated ; of the 79 remaining women and children none were inoculated. 
This would make the unattacked who were uninoculated about 100 less than the number given by 
Mr Maynard and would increase the correlation. The report, however, in its present form is not one 
from which it is easy to draw any definite conclusions. The actual proportions of the inoculated and 
uninoculated in the Delhi squad are not given, although it is possible that the visit contributed to the 
outbreak. It is not clear how far the draft of the regiment numbering 96 which reached India two 
months later is or is not included in the returns of cases. If wholly uninoculated, it would account 
for the 96 additional persons in Mr Maynard's table, but some at least appear to have been inoculated 
(Luxmore, p. 492). If cases of enteric among this draft are included among the last 20 cases reported 
by Luxmore, then the total -593, given on his p. 492, does not apply to the incidence. Lieutenant-Colonel 
Leishman writing in the same Journal, p. 465, of the outbreak in the 17th Lancers at Meerut says : 
" The report of the attached medical officer. Lieutenant Luxmore, furnishes a striking piece of 
evidence as to the protective effect of the inoculations The uninoculated portion of the regiment 
served, unintentionally, as ' controls " and the fact that of 63 cases 61 occurred among these controls, 
and only two among the inoculated men of the regiment, is one the significance of which it is hard to 
minimise." 
According to Lieutenant Luxmore's Iteijorl, there were only 61 cases (.59 uninoculated and two with 
the first inoculation dose) not 63. Without knowing the totals of inoculated and uninoculated in the 
regiment it would not be easy to express the significance really borne by Lieutenant-Colonel Leishman's 
statement. But several other points of view may be suggested of the 150 inoculated; 13 per cent, were 
ofheers and officers' wives, whose environment and average age probably differ much from those of the 
non-commissioned officers and men. Of the 150 inoculated two were attacked ; of the 79 uninoculated 
women and children included on the strength of the regiment only one appears to have been attacked, 
a rather less percentage than in the case of the inoculated. Further the so-called "controls" cannot 
be considered as true controls, until it is demonstrated that the men who are most anxious and 
particular about their own health, the men who are most likely to be cautious and run no risk, are 
not the very men who will volunteer to be inoculated ; thus a spurious correlation may be produced 
between attack and absence of inoculation. The age frequency of both classes ought to be further 
given in every report. Clearly what is needed is the inoculation of one half only of the volunteers, 
equal age incidence being maintained, if we are to have a real control. The subjection of the inoculated 
and uninoculated to exactly like conditions of service ; the exclusion of officers and their wives, and the 
women and children from the strength on which percentages are based (and the discovery if possible of 
why these classes are relatively immune !). Useful points even as statistics are now given would be the 
addition of the age frequencies and the sickness record (other than that of enteric) of the inoculated and 
uninoculated groups. Until a far higher standard of statistical observation and statistical reduction is 
adopted, we cannot possibly call, with Lieutenant-Colonel Leishman, the Eeport of Lieutenant Luxmore 
a striking piece of evidence as to the protective eifect of the inoculations. What is needed at present in 
the Army Medical Department is a trained statistician alongside the trained bacteriologist. Euitoh.] 
