AW: [ RadSafe ] query
Rainer.Facius at dlr.de
Rainer.Facius at dlr.de
Fri Jan 11 03:54:37 CST 2008
Bernard:
RELATIVE RISK:
Relative risk is a ratio (the risk of cancer for a given radiation dose, divided by the background risk)
EXCESS RELATIVE RISK:
Another way of expressing risk is excess relative risk. This is figured by subtracting 1 (that is, the background risk) from the relative risk.
(http://www.doh.wa.gov/Hanford/publications/overview/risk.html)
Thereby:
R(D) = R(0) [ 1 + k D ]
RR(D) (relative risk) =: R(D)/R(0)
ERR(D) (excess relative risk) =: RR(D) - 1
ERR(D)= RR(D) -1 = R(D)/R(0) - 1 = k*D; q.e.d.
"But this is hard to believe"
Mathematics (fortunately) is the one exception in science, where belief is irrelevant - once the definitions are set.
Check your paper whether the definitions pertain.
Best regards, Rainer
________________________________
Von: radsafe-bounces at radlab.nl im Auftrag von Bernard L. Cohen
Gesendet: Do 10.01.2008 18:59
An: RadiatSafety
Betreff: [ RadSafe ] query
Can someone help me on this question -- please reply to blc at pitt.edu.
If rhe risk of cancer, R, is expressed as
R = R(0) [ 1 + k D ]
where R(0) is the risk with no exposure, D is the dose in Sv, and k is a
constant, what is the excess relative risk, ERR. I thought it would be
ERR = k. In that case, a finding that ERR = 1.0 / Sv would mean that the
risk is 2R(0) for an exposure of 1.0 Sv, 3 R(0) for an exposure
of 2.0 Sv, 4R(0) for a dose of 3.0 Sv, etc. But this is hard to
believe in a paper I am trying to understand. Any help on this would be
appreciated
--
Bernard L. Cohen
Physics Dept., University of Pittsburgh
Pittsburgh, PA 15260
Tel: (412)624-9245 Fax: (412)624-9163
e-mail: blc at pitt.edu web site: http://www.phyast.pitt.edu/~blc
_______________________________________________
You are currently subscribed to the RadSafe mailing list
Before posting a message to RadSafe be sure to have read and understood the RadSafe rules. These can be found at: http://radlab.nl/radsafe/radsaferules.html
For information on how to subscribe or unsubscribe and other settings visit: http://radlab.nl/radsafe/
More information about the RadSafe
mailing list