[ RadSafe ] Cohen's radon results differently

Bernard L. Cohen blc at pitt.edu
Tue Sep 20 12:20:35 CDT 2011

My analyses excluded the retirement states, Florida, California, and 
Arizona, although including them did not change the results. I did 
present evidence that movement of people was not a serious problem, but 
I do not remember the details; it gave data on distance from death 
location to where most of their lives were spent. I can look this up if 
you consider it to be very important.

On 9/19/2011 7:20 PM, Brennan, Mike (DOH) wrote:
> Another confounder, I would expect, is the movement of people.  For
> example, my in-laws moved to a retirement home near us, about two years
> before my mother-in-law died (not of cancer).  Any statistics pegged to
> the county in which she died would introduce error into any study other
> than one about end-of-life care, as the conditions in this county have
> nothing to do with here long term health.  I would estimate that well
> over half of the people at this large retirement facility are from out
> of the county, and not a few from out of the state.  This effect has to
> be even greater for places like Florida.
> The unlikely political bedfellows of Hilary Clinton and Newt Gingrich
> have teamed up to support a national health records program (though
> neither has spoken much about it recently).  The cost savings, both in
> lives and in money, would be substantial, but I see even greater
> possibilities in terms of being able to get MUCH better data for studies
> such as this.  Imagine if instead of estimates of smoking prevalence you
> could CONTROL for smoking habits of the case and control cohorts.
> There are people who contend that such a system is too much of an
> intrusion into privacy, and that the couple tens of thousands of people
> who die each year due to incomplete or inaccessible medical records is a
> fair price to pay.  While I don't think they are right, I think they
> will probably win until the Facebook generation takes the lead.
> -----Original Message-----
> From: radsafe-bounces at health.phys.iit.edu
> [mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Bernard L.
> Cohen
> Sent: Monday, September 19, 2011 3:55 PM
> To: Chris Hofmeyr
> Cc: radsafe at agni.phys.iit.edu; WesVanPelt at verizon.net
> Subject: Re: [ RadSafe ] Cohen's radon results differently
> To do anything, I would need some credible source of smoking prevalence
> data. I tried several and they did not change my results. Please suggest
> an alternative.
> On 9/18/2011 3:31 PM, Chris Hofmeyr wrote:
>> Radsafers,
>> On 19th June Howard Long challenged my reminder that in Cohen's
> US-wide study
>> of domestic radon and lung cancer, there was, on average, a negative
>> correlation between Cohen's smoking prevalence and the average county
> radon
>> concentration. Howard wanted numbers.
>> On 20th June prof Cohen invited further discussion of his work.  Then
> away on
>> an extended stay, I told dr Long that I will have a look when I get
> back home.
>> B Cohen and Wes van Pelt had kindly made their data available in
> spreadsheet
>> form almost a decade (and a few computers)ago. At the time and later I
> did
>> numerous plots and wrote some notes, which I now found on an archive
> disk.
>> I put some of it together in a .pdf file of about 1.5MB (attached);
> please
>> excuse some repetition in the text. If the attachment does not survive
> Radsafe,
>> then please request directly from me at webmail address below.
>> Some background for the younger crowd:
>> Cohen set out to study lung cancer rates as a function of county
> average
>> domestic radon concentration (ARC)in 1601 US counties. His null
> hypothesis was
>> presumably to justify LNT (Linear No-Threshold model of
> carcinogenesis).
>> However, fate stacked the cards in that smoking prevalence, as
> determined by
>> him, was to a degree anti-correlated with average county radon. Due to
> the
>> carcinogenic strength of smoking, the raw data naturally reflected an
>> anti-correlation with radon concentration.
>> This meant that the lung cancer data would have to be carefully
> corrected to
>> extract a 'real' correlation, which Cohen probably only realized when
> he was
>> analyzing the data. Cohen tried more than one avenue to assess smoking
> prevalence
>> and he was obviously reasonably satisfied with his final choice,
> although his
>> correction strangely left the anti-correlation practically unchanged.
>> Having investigated lung cancer (LC) - Cohen's and Van Pelt's data -
> also in
>> relation to elevation and county population size, I am practically
> forced to
>> the conclusion that there appears to be a strong smoking residual even
> after
>> the correction. LC shows an even stronger anti-correlation with
> altitude below
>> 1260ft than with radon (ARC) below about 3pCi/L,yet (LC) proves
> independence of both.
>> Cohen tested several hundred possible confounders, but very few
> managed to turn the LC
>> correlation with Average radon positive.
>> I would respectfully ask prof Cohen: SUPPOSE the smoking correction
> was
>> insufficient and left an implicit smoking component in the LC data?
>> In the notes I explain how one can use a plotting trick on Cohen's
> data to
>> evaluate LC dependence (or rather independence) on ARC even without a
> smoking
>> correction to the LC data - and consequently dispose of LNT.
>> Regards
>> chris.hofmeyr at webmail.co.za<mailto:chris.hofmeyr at webmail.co.za>

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

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