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are recorded by local registrars and by them reported to the Registrars-General. It is
thus possible to obtain the total number of deaths of men stated to be seamen, but in
connection with civil registration it is necessary to ascertain whether the decedents
could, at the time of death, be accepted as seamen within the Board of Trade definition.
Accordingly copies of all entries relating to deaths of seamen reported to the
Registrars-General at any time between 1st October, 1929, and 30th September, 1930,
were sent to the Board of Trade for information as to the date of the last sea service
of the deceased and for decision as to whether he was correctly described as a seaman.
If the Board of Trade had no records of the decedent, local enquiries were made.
As a result, 16.3 per cent. of the recorded deaths were rejected as not being of
seamen within the Board of Trade definition. The total number of deaths thus accepted
as of British seamen in the year under review was 3,166. Taking the population at
risk as that obtained from the Annual Census of Seamen on 31st March, 1930, this
gives a mortality rate of 24.8 per 1,000. Basing the population on the figures obtained
from the General Census of 1921 the mortality rate is 17.61.
Calculations of the mortality amongst lascars and foreigners are obviously of no
value, because "large and unknown numbers of these men having served on British
ships retire to their native countries and die there."
Eighty per cent. of deaths were due to disease; 6 per cent. to injury and accident;
4 per cent. to old age; and 3 per cent. to suicide. Diseases of the respiratory system
are responsible for 20 per cent. of all deaths, of the circulatory system for
19.6 per cent., cancer for 11 per cent., diseases of the digestive system for
5.4 per cent., and of the genito-urinary system for 6.2 per cent. Fundamental
differences between service in the Navy and in the Mercantile Marine render
dependable comparisons between the mortality rates extremely difficult. Comparison
is only possible if mortality rates for the Mercantile Marine are calculated by relating
the deaths of British seamen at sea and in ports abroad to the population as
enumerated at the Annual Census of Seamen, and on this basis the rates for the
Merchant Service compare favourably with those for the Navy.
Lack of accurate information regarding population and age distribution and the
small number of deaths investigated prevents the use of the method of a standardised
population for comparison between mortality rates in the Merchant Service and in
shore occupations, and the author has been obliged to resort to the method of
proportionate mortality. In this way comparisons are made with a number of shore
occupations in which a high standard of physical fitness is demanded : Coal Miners,
Agricultural Labourers, Carmen, Carriers, &c., Railway Engine Drivers, Stokers, &c.,
Dock Labourers. It appears that though respiratory diseases are one of the principal
causes of death the mortality from this cause at all ages in the Mercantile Marine is
below the average in the selected occupations; in circulatory diseases there is an
excess mortality at age 55-65 and a considerable excess at 65 and over; diseases of
the digestive system are slightly above the average, particularly from 35-45. Cancer
is below the average except between 35 and 45 and over 65. Mortality from genitourinary
diseases is slightly in excess between 35-45 and over 65. Accidents are an
excessive cause of mortality, particularly up to age 35. Suicides also are excessive
at all ages. Alcoholism is not a more frequent cause of death than in the selected
shore occupations.
It therefore appears that service in the Mercantile Marine is no more inimical to
life and health than are many of the occupations ashore frequently regarded as
healthful, indeed, in many instances it has been shown that the advantage distinctly
lies with the seaman.
The author concludes that the whole scope of enquiry must be widened if
dependable conclusions are to be reached, the data should relate to more than one
vear and more time must be allowed for their analysis.
The difficulties experienced by an expert statistician in investigating this question,
even when special facilities were afforded to him, show that conclusions based on the
data ordinarily available are of little or no value.