RE: Cohen's Ecologic Studies

["Marco Caceci" <mcaceci@radal.com>]

I thought that that was the point: if you assume LNT (or just use, as

stated, "the false premise of linearity") you discover that hormesis exists.



I consider the abstract below loaded with innuendo and meant to be

unintelligible, but this is how I read it:

- you cannot plot cancers against dose(rate): that is assuming linearity

- hence your conclusions are wrong

the logic sounds funny to me, and particularly so if the argument is (as it

will be) used to defend the LNT model which is linear (but leans the wrong

way).



I have no problem in admitting my ignorance of much statistics, also I have

not read the paper, but I have seen enough data to accept linearity at low

doses (and argue for that: heard of Taylor's expansion?) and to accept that

hormesis is there.



You cannot contraddict the facts (or can you?), and the facts are that

higher environmental dose rates are (ecologically, statistically, whatever)

associated with lower (lung) cancer rates.



It used to be that only original, experimental, scientific results (as

opposed to ideas and (re)calculations) were accepted for publication on

respected scientific journals.



Enough said, please don't flame me, I do not particularly wish to restart a

thread I was glad to see closed, but I just must take sides sometimes when

dogma fights evidence.



My respect is all for Professor Cohen, his results will always carry quite

well, IMHO, the burden of their ecological fallacy.



Marco



----



Radiol. Prot. 22 (June 2002) 141-148

The potential for bias in Cohen's ecological analysis of

lung cancer and residential radon

Jay H Lubin

.... (NIH!?!?!?)

Although several authors have demonstrated that risk

patterns in ecological analyses provide no inferential

value for assessment of risk to individuals, Cohen

advances two arguments ... who suggest

!!!

Cohen's results are and will always be burdened by the

ecological fallacy.

!!!

....

Average dose determines

average risk only for models which are linear in all

covariates, in which case ecological analyses are valid.

However, lung cancer risk and radon exposure, while

linear in the relative risk, are not linearly related to

the scale of absolute risk,

!!!!

and thus Cohen's rejection

of the LNT model is based on a false premise of

linearity.

!!!!

....







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