Hi
here's some figures for you. I have extracted these from several
sources at the US National Center for Health Statistics.
Infant mortality is usually defined as death before the first year of
life is completed. For the examples I have used only the figures for
white males to avoid having to calculate overall averages for the
earlier figures and because it seems to me these figures are likely to
be the least affected by social factors (see discussion below).
Infant mortality is usually defined as death during the first year of life.
So to exclude the effect of infant mortality you need to know the
change in life expectancy in individuals who have reached age 1. I
have also included the life expectancies from age 20 as an arbitary
exclusion of childhood diseases and at age 40 for those entering
mid-life crisis.
Average Remaining Lifetime In Years At Specified Ages, US White Males
Age 1900-02 1949-51 2002
0 48.23 66.31 75.1
1 54.61 67.41 74.6
20 42.19 49.52 56.1
40 27.74 31.17 37.4
So, as you can see you are correct when simply excluding infant
mortality and even for greater ages.
However as to causation the relationships may be even more subtle than
you might have thought.
It is going to depend a lot on what you consider 'modern science' and
'medical science'. Much of the improvement in life expectancy is not
due to 'medical science', but rather to other scientific/technological
effects and their interaction with economic and social ones. So it is
possible that more important roles are played by water supply and
sewerage, nutrition, etc than by strictly medical intervention.
e.g. from http://www.allen-unwin.com.au/extracts/pdfs/0335199216.pdf
"As can be seen from Figure 1.1, which depicts the fall in standardized
death rates for the nine common infectious diseases in relation to specific
medical measures for the United States, the decline in mortality from
these major infectious diseases took place before effective medical
interventions became available. McKinlay and McKinlay (1981: 26)
concluded
from their analysis that ?medical measures (both chemotherapeutic and
prophylactic) appear to have contributed little to the overall decline in
mortality in the United States since about 1900 . . .? Similar conclusions
were reached by McKeown (1979) on the basis of an even more extensive
analysis of data from England and Wales."
the relevant references for the above quote are:
McKinlay, J. and McKinlay, SM (1981) Medical measures and the decline
of mortality. In: H. Freeman and S. Levine (eds) Handbook of Medical
Sociology, 4th Edition. Englewood Cliffs, NJ: Prentice Hall.
McKeown, T. (1979) The Role of Medicine. Oxford: Oxford University Press.
Teasing out the contribution of all these factors to the changes in
life expectancy is indeed a subject worthy of many PhDs. |