[ RadSafe ] Re: "-authors do not report-" data refuting their conclusions!

[John Jacobus]

So, you say we should look for hormesis?  Would that
not lead bias the analysis?

>From looking at the McGregor and Lan reports, it seems
clear that they were trying to correlate radiation
dose to breast cancer.  They did find this a
correlation.  However, I do not see any suggestion in
their data of a predisposition to demonstrate a
harmful effect at low doses.  In fact, they are silent
on dose effects below 17 rad.  Read the discussion.

Could it be that you are biased?  If not, how do you
explain the data in the attachment I sent you from
their 1977 report?  Do you think they made up the
data?

--- howard long <hflong at pacbell.net> wrote:

> John , then, people were not looking for hormesis.
>  
> With the numerous suggestive evidence, now seeming
> overwhelming, we now should.
>  
> Best Wishes,
> Howard
> 
> John Jacobus <crispy_bird at yahoo.com> wrote:
> I am sorry you do not agree. Maybe others some
> insight into which of us is wrong with interpreting
> this report.
> 
> I think it is very bold of you to say the authors
> biased the data. Do you have any proof of this
> expect
> that you do not like their conclusions? Did you see
> the other paper, or do you think that data is also
> biased?
> 
> --- howard long wrote:
> > John, I disagree with your interpretation.
> > 
> > Prejudice is the authors. They set up data so that
> > only harm and not benefit would show, as
> everything
> > below a dose, column 1, Table 2.
> > 
> > Fortunately, the data in the rows isolates by dose
> > both above and below, allowing the clear 
> > J curve of data, refuting LNT.
> > 
> > Howard 
> > 
> > John Jacobus wrote:
> > Again, the left column represents the data in that
> > range of doses. The rows represent the extent of
> the
> > analysis. It the bottom row of first section,
> > considers the analysis of only two columns of
> data,
> > 0
> > and 0-9 rad. The trend test and value P shows how
> > well the curve fits the data. As you go up the
> row,
> > more data is used to develop the curve, and as you
> > can
> > see the test of the curve fit gets better through
> > the
> > whole range of data, even if it gets worst at the
> > lower ranges. 
> > 
> > I do not know what you mean by the "one-tail
> test."
> > I
> > believe what you are referring to is the
> chi-squared
> > test. However, I believe that they are using some
> > other correlation test to evaluate the fitting of
> > the
> > dose to the cancer incident in table 2, which is
> not
> > the same thing. The analysis of the fit results
> the
> > P-value, which they discuss under "Results" on
> page
> > 19. Since you used to study epidemiology, I assume
> > you understand their analysis.
> > 
> > The point that I am making is that the observed
> > cancers does not change in any one column.
> However,
> > the expected value changes as a new curve is
> > developed
> > for the data used. In the bottom row of the first
> > section, the expected and observed cancers are
> > equal. 
> > One could say that at the 0-9 rad dose levels, the
> > LNT
> > is a good predictor of radiation effects. As you
> add
> > higher doses, the LNT is less so, which is not
> > surprising as there is a lot of "noise" data based
> > on
> > the P value from the bottom row of the first
> > section. 
> > However, as I have mentioned, the expected is only
> a
> > mathematical projection. While the actual number
> of
> > cases may, as you say, not fit the LNT hypothesis,
> > that is not be the complete story. For the lowest
> > row
> > in the first section, it does a very good job. 
> > 
> > If you want to look at the epidemiological data
> that
> > compares expected and actual cancer in the
> > population,
> > you should look at the one page from McGregor and
> > Land
> > report of 1977 that I have attached. 
> > 
> > My point is that you have to be clear in what you
> > say.
> > The fact is that x numbers of cancers were
> observed,
> > which is a fact. However, when you say expected in
> > this study, the expected is based on intrapolation
> > from the data. It is not epidemiological data
> which
> > is what you should be comparing the observed with
> > the
> > expected. From the McGregor and Land paper of
> 1977,
> > the attachment, it appears that there is no
> > beneficial
> > effect from doses of 0-9 rad. 
> > 
> > When you say that the number of observed is
> > different
> > from the number expected on the top line, I would
> > ask
> > what is the basis of you expected number? This is
> > good science and not data mining.
> > 
> > -- John
> > 
> > --- howard long wrote:
> > > John,
> > > The left column, labeled "Dose range kerma",
> > unlike
> > > the rows, covers dosage from a given level to 0.
> > > That is consistent with their one-tail test,
> which
> > > assumes that any radiation under the specified
> > > amount gives increased risk of cancer. 
> > > 
> > > Their own top rows of O and E do not fit that
> LNT
> > > hypothesis.
> > > 
> > > Howard 
> > > 
> > > John Jacobus wrote:
> > > The question is this.
> > > As you look down the columns of table 2, the
> > > observed
> > > cases stay the same. However, the expected
> number
> > of
> > > cases change. I say that this is due to the use
> of
> > > the data to draw linear curves thought the data
> > > sets.
> > > 
> > > Do you agree or do you have another explanation?
> > 
> > 
> > 
> > 
> > 
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> 
> +++++++++++++++++++
> "A positive attitude may not solve all your
> problems, but it will annoy
> enough people to make it worth the effort." Herm
> Albright
> 
> -- John
> John Jacobus, MS
> Certified Health Physicist
> e-mail: crispy_bird at yahoo.com
> 
> 
> 
> __________________________________ 
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> 


+++++++++++++++++++
"A positive attitude may not solve all your problems, but it will annoy
enough people to make it worth the effort." Herm Albright

-- John
John Jacobus, MS
Certified Health Physicist
e-mail:  crispy_bird at yahoo.com


		
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