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Re: A clarification following John Jacobus's comments about mynewsitem.



Dear Bill Field and List,
Misuse of Field's excellent Iowa study - radon level in homes of lung cancer cases vs controls - was the reason for my bringing it into this thread. Difficulty in matching controls, is the reason for double blind placebo studies. Field's matched controls had c 35% smokers vs c 95% smokers among cases (if I recall correctly). This leaves doubt about the validity of a statistical correction for a confounder (smoking) 10 x as great as the test item (radon).

More important, The American Cancer Society is proclaiming, "Radon Causes Lung Cancer", from Iowa findings, selecting, then extrapolating beyond the data (as with LNT and ALARA). In the  USA as a whole. Iowa is a 1% outlier, with the highest mean county radon in the USA, as stated by Field. Iowa is the only place Cohen found in USA not showing clearly LESS lung cancer mortality where average home radon was more. Iowa cases had c 5pCi/L and controls c 4 pCi/L. USA county lung cancer mortality was least around 3pCi/L and highest under 1 pCi/L. USA average is c 1.3 pCi/L.  I conclude, 1, Iowa cases may have had less hormesis at 5 pCi/L than controls at 4 pCi/L, 2, MORE radon in USA homes with under 1pCi/L would result in LESS lung cancer.

These are not "allegations" about Field's study, but of its misapplication. In fact, I think that Field and Cohen together may have found the best dose of an under-used medicine - radon. note: Becker believes that in Europe, the best dose may be much higher, and he may be correct. I'll defer clarification of my belief that estrogen-progestin protects from cardiovascular disease in never smokers.

Howard Long

epirad@mchsi.com wrote:

Howard,

I again do not understand your comments below.  Could
you be more specific with your allegations if you are
going to reference my name?

Bill Field
bill-field@uiowa.edu
> John J,
> Cameron was one of the Technical Advisory Committee of NSWS and more familiar
> with it than most authors of most "peer reviewed articles" of their studies. His
> insights are most revealing about political deceipt in the reporting of the
> data.
>
> As an epidemiologist, I consider the data and inferences he presents as about as
> good as one can get short of placebo controlled studies - or ones with better
> "matched" controls than Field's 35% smokers vs 95% of lun cancer cases. Even
> placebo studies can distort application, as mingling ever-smokers (400% CV
> mortality after age 45 of never-smokers using estrogen-progestin)) for Prempro
> use or placebo, then decreeing never-smokers also should not use Prempro to
> reduce CV mortality, because of 130% incidence of CV disease for combined group.
> Prempro may reduce CV mortality in never-smokers, I believe.
>
> I believe Cameron is right, and, in the right dose, ionizing radiation, like
> sunshine, is an essential trace energy
>
> Howard Long
>
> John Jacobus wrote:
>
> > John,
> > I have read your letter to the BJR.  (Actually, I have read it the first
> > time you sent it to me and the previous letters that you have sent to
> > different newsletters.  I guess no one else has read them, or else they
> > would have been referenced by others beside yourself.)  Again, it is a
> > letter, which certainly does not carry the weight of a reviewed article.  It
> > carry the same impact as the "letters to the editors" we see in the local
> > papers.  Because I have read this letter I thought our readers should not be
> > lead into believe that is based on any proper peer review.  (I have yet to
> > see a "letter to the editor" peer reviewed.)
> >
> > The fact that your BJR letter "presented information not contained in the
> > original article" does not mean it is true.  If they are so startling, why
> > did the authors not see it?  Maybe they did not see the "good news" because
> > there is none.  Have YOU contacted the authors with your revelations?  I
> > believe that Berrington, Doll and associates are reasonably intelligent men.
> > As epidemiologists who have collected the data, they may even give you
> > insights into how their drew their conclusions and what the limitations
> > might be.  It might even be possible that this 36% difference in non-cancer
> > death rates is not considered significant based on the actual numbers.  Of
> > course, there could be a conspiracy to hide the "good news."
> >
> > I am not an epidemiologist, but I have been trying to learn a little about
> > the science.  As mentioned in the article, there are many sources of bias in
> > these studies that the epidemiologist has to consider.  It is not just the
> > statistics.  Again, I refer you to EPIDEMIOLOGY, November 1999, Vol. 10, No.
> > 6, "What You Should Have Learned >about Epidemiologic Data Analysis" at
> > http://ipsapp002.lwwonline.com/content/getfile/64/35/1/fulltext.htm and
> > EPIDEMIOLOGY 2001;12:114-122, "Causation of Bias: The Episcope" at
> > http://ipsapp002.lwwonline.com/content/getfile/64/48/19/fulltext.htm.  I do
> > not claim that will give you the skills to be an epidemiologist, but I did
> > learned things that the improved my evaluation skills.
> >
> > For example, the Berrington, et. al. paper does not present dosimetry data.
> > Do you think that kind of information is important?  In this country there
> > are radiologists who get little or any radiation exposure after their
> > residency programs.  Specifically, those who read mammography screening
> > films and CT or MRI images.  Maybe a number of these are in the 1955 to 1972
> > and newer groupings.  I would expect exposure values should be considered
> > among the radiologist.
> >
> > Another example was the control for confounding factors, like smoking.
> > Besides lung cancer, smoking contributes to heart and cariovascular disease.
> > Is there a correlation between non-cancers and smoking rate between
> > radiologist and non-radiologist MDs?
> >
> > Whether or not I think the "good news" about radiation should be mentioned
> > is not my concern.  I try to base my conclusions on the science and the
> > data.  I do not try to jump to conclusions about other researchers' work
> > without knowing all of the facts.  It is good science v. "data mining."
> >
> > -- John
> > John Jacobus, MS
> > Certified Health Physicist
> > 3050 Traymore Lane
> > Bowie, MD 20715-2024
> > jenday1@email.msn.com (H)
> >
> > John Cameron wrote:
> >
> > Dear Colleagues, I don't object to John Jacobus's comments but it
> > appears that he did not bother to read my letter to the BJR which was
> > readily available and compare its contents to the copy of the
> > original article which he has on hand. I suspect that most of the
> > readers of the news release are not as well informed as John Jacobus
> > is about radiation effects.  Most of the readers of the original
> > article probably did not study the data in Table 2 to see the good
> > news.
> >
> > My letter to the BJR presented information not contained in the
> > original article on British  radiologists. It is true that all the
> > data I presented were in the original Berrington et al article but
> > they  were ignored by the authors. They stated that there was no
> > evidence that radiation had an effect on any disease other than
> > cancer. They didn't mention that British radiologists who entered the
> > field from 1955 to 1979 had a non-cancer death rate 36% lower (i.e.,
> > they lived over three years longer P<0.001) than other male MDs in
> > England.  That sure looked like an effect on non-cancer to me. That
> > news was not mentioned in the Aug. 25, 2001 Lancet last year because
> > The Lancet commentator just read the conclusions and did not study
> > Table 2 to see the health improvement. I doubt if The Lancet
> > commentator will write another column pointing out the good news. (I
> > sent The Lancet a copy of my letter to the BJR so they would be aware
> > of the omission of the good news.) Perhaps no one wanted to criticize
> > an article with Sir Richard Doll as an author.
> > The authors of the 100 years of British radiologists study
> > used the same trick as Matanoski in the narrative of the NSWS final
> > report where she reported that the nuclear workers had not suffered
> > any ill effects of radiation at "this time". She made no mention of
> > their improved health.  It is inappropriate to have good news in the
> > data and not mention it.
> > Maybe John doesn't think that good news about radiation
> > should be mentioned. Why did no other person call this good news to
> > the attention of BJR readers during the last year?  it is significant
> > that the authors of the article chose not to rebut my comments. If
> > the British radiologists had clear health risks from radiation it
> > would have made the news.
> > Best wishes, John Cameron