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From the total "estimated deaths" and the cases notified at "all ages,'' a "standard casemortality"
for each month has been calculated, the differences in which are solely due to differences in
the age and sex distribution of the cases notified. By dividing the "all ages" case-mortality of the
period 1892-5, viz., 4.47, by each of these "standard case-mortalities," a factor is obtained for
correcting the case-mortality of each month (calculated from notified cases and registered deaths) for
differences in the age and sex distribution of the cases notified. The result of these calculations is
shown in the following: table—

It will be seen from a comparison of columns 5 and 6 of this table that the variation in the
case-mortality at different periods of the year is but slightly affected when correction is made for
differences in the age and sex distribution of the disease; in other words, the variations in the age and
sex distribution of the disease at different periods of the year are wholly insufficient to account for the
striking differences in case-mortality shown in column 5 of the table.
It is interesting to observe(diagram VIII.)that the fatality of the month of August causes an interruption
to the fall from the maximum to the minimum. This increase of the fatality in August appears
partly explicable on the hypothesis that owing to the decrease, as the result of the summer holiday, in
that month of the prevalence of scarlet fever among school children whose fatality rate is comparatively
low, the cases of the month contain a larger proportion of younger children whose fatality rate is comparatively
high, and hence the fatality of the month at "all ages" is disturbed by an exceptional
age distribution. An examination of column 6 of the table shows, however, that this explanation is
only partial, and that even when correction is made for the exceptional age and sex distribution of the
cases notified in August, the case-mortality of that month still causes an interruption in the fall of the
curve of case-mortality, although this interruption is considerably modified after correction. Experience
of the statistics of a greater number of years is evidently required to show whether this increase of
fatality will be maintained.
The use of hospitals.
Reference to diagram VII. shows that in 1895 there was a slight decrease in the proportion of
the cases of scarlet fever which were admitted into, and the proportion of deaths which occurred in the
hospitals of the Metropolitan Asylums Board, as compared with 1894. In 1895 the number of cases
admitted into the3e hospitals was 11,271, or 57.0 per cent. of the total cases notified, and the number
of deaths occurring in these hospitals was 591 or 71.3 per cent. of the total deaths registered in
London from this disease.
Scarlet fever and elementary schools.
In diagram IX. I have shown, as in previous reports relating to other years, the number of cases
of scarlet fever notified in each week of 1895 in relation to the mean of the year. The diagram shows
a marked diminution of prevalence in the month of August, which I attribute to diminished
opportunity for the dissemination of the disease by schools in that month as the result of the closure
of the schools for the summer holiday. The summer holiday of the London School Board schools
began in 1895, at noon, Thursday, 25th July, or the latter part of the 30th week, and reopened on
Monday, the 26th August, at the beginning of the 35th week. The curve shows a fall in the number
of cases notified in the 31st week, and an increase in the 36th week. If the number of cases notified
in the four weeks which would be most subject to the influence of the holiday, i.e., the 32nd to 35th,
be compared with the number of cases notified in the four preceding and four subsequent weeks.