In article <[log in to unmask]>, Hideki Nomura
<[log in to unmask]> writes
>Gary Jackson, Toby Lipman and Rod Jackson claim that
>we should multply the risk reductions. Sounds reasonable.
>
>But as James McCormack commented, probably exept the UKPDS
>example Craig Currie provided, I have not seen any epidemiological
>evidence to justify this calculation.
Dear All,
It strikes me that there is a real danger of thinking that we understand
more than we do. Clearly the relative reductions cannot be added. In
addition, it is possible that the interaction between risk factors does
not operate constantly at all risk factor levels. To illustrate. I
gather that the relative risk for CHD associated with smoking is not
very marked in populations where cholesterol levels are low. It is
possible that, for individuals with low cholesterol the risk associated
with changes in other factors may not multiply in the same way that they
would for an individual with a high cholesterol. I am not saying they
don't, just that we don't know. We also may never know....
--
Ian Bowns
Senior Research Fellow
Health Policy and Management
School of Health and Related Research (ScHARR)
University of Sheffield
Regent Court
30 Regent Street
Sheffield
S1 4DA
Tel; +44 (0)114 2220742
Fax; +44 (0)114 2220798
E-mail; [log in to unmask] (work)
E-mail [log in to unmask] (home)
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