MadSci Network: Medicine |
Dear Ole,
I believe this is called the Glaister equation - the version that I have is 98.4, rather than 98.5. I find equations are best understood by plotting them, so I did a simple plot, plugging the values 90, 80, 70, 60 and 50 for rectal temp into this equation. I have uploaded an image of the plot for you.
What we see is that this equation describes a rather simple relationship in which time of death increases linearly with the difference between the normal body temperature of a living person (98.4 degrees F) and the measure rectal temperature. In fact, the 1.5 comes from the assumption that the body will cool by 1.5 degrees per hour after death.
There is a very good detailed discussion of estimating time of death and
how simple formulae such as this can be very wrong at this link:
http://www.dundee.ac.uk/forensicmedicine/llb/timedeath.htm
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