ecological fallacy and the LNT

[RuthWeiner@AOL.COM]

Dear RADSAFERs


I am working my way through both Field et al (and some ancillary papers kindly sent me by Dr. Field) and Dr. Cohen's papers (thatnk you, Bernie, for sending them).  I am trying to understand the papers with all their nuances.  I believe this can be done by a reasonably competent scientist like me (Ph. D. -- chemistry) without special training in epidemiology, but from time to time I will post questions -- real questions to which I would like real straightforward answers -- on RADSAFE.  Let me say at the outset that these questions are not intended to castigate anybody or take sides.  If I use the LNT in a question, it doesn't mean I endorse it.   The questions are for information.   (and if they sound repetitive to the individual who accused me of "me too-ism" well, that can't be helped).  So here is my first question, about the "ecological fallacy."


Let us say the cumulative dose to a population of 10,000 persons is 1000 PERSON-rem.  Then, according to the LNT, one might expect 0.5 excess cancer in that population of 10,000 (0.0005*1000 = 0.5).  One can also, independently, say that the average dose is 0.1 rem (1000/10,000 = 0.1), or 100 mrem.  But to say that therefore the average expected cancer incidence would be 0.000005 (0.0005*0.1) is the fallacy in question.  Essentially, "average individual cancer expectation" or whatever is meaningless.  Have I got it right?  If not,what is my mistake?


(The LNT conversion from rem to cancer is from ICRP 90, page 22)


Ruth Weiner, Ph. D.

ruthweiner@aol.com