Re: Wing: Descriptive Epidemiology by Any Other Name...

[muckerheide@highway1.com (James Muckerheide)]

Bob Flood wrote:
> 
> At 04:39 PM 2/26/97 -0600, Dan Strom wrote:

> >If you are upset by Wing yet celebrate Cohen, I ask that you examine why
> >descriptive studies are compelling in one case and not in the other.  To
> >me, the bottom line is that neither have data for individuals, neither
> >has meaningful control for confounders and biases, and no amount of
> >statistical analysis will change that.  Both fail to meet many of the
> >criteria presented by leading risk analysts.
> 
> A point well made - the methodology cannot be acceptable in one case and
> inappropriate for the other.

Bob, This "logical", but Dan's premise is utterly false. This is NOT a
matter of an "unacceptable methodology". This methodology is used VERY
extensively in science. Only in "radiation science" is this polemic
argument made to misrepresent the significance of the obvious. See my
previous message about EPA's extensive use of this methodology in its
current and previous regulatory work. Look at the NIH and CDC extensive
data and analysis on US health, nad the analyses and conclusions of many
variables and outcomes that depend wholely on this kind of analysis. (We
know that the radiation health effects 'leadership' know this full well,
but the rhetoric is politically effective and picked by those who just
repeat the mantra. 

> However, it is important to note that the description given cited the
> descriptive study as suitable for developing a hypothesis. Well, LNTH mean
> Linear No Threshold HYPOTHESIS, and the Cohen data point directly to a
> contradictory hypothesis. 

As has been stated often, most strongly by Bernie Cohen himself, and in
very specific language in his articles: in your terms above, Cohen's
data and results point to NO hypothesis at all!

Cohen's analysis tests the linear hypothesis. The linear hypothesis is
subject to this test because the very idea of a no-threshold effect, and
its associated "collective dose" MEANS that the mean dose to a
population is associated with total effects. Cohen in no way concludes
or proposes another hypothesis. (Please see Cohen's Feb 95 HPJ article,
and his 1/97 HPJ article.)
 
What the data unamiguously determine, in the absense of any indicated
weakness in the analysis (and has been stated in the HPJ, here, and
elsewhere many times: No weakness in the data or the analysis has been
identified (again, HPJ 2/95, 1/97, and forthcoming HPJ (May?)) - with an
offer, now at $2500 for any alternative explanation of the data (by the
supposed "scientists" who trash Bernie personally and his analysis by
the bureaucratic network and innuendo, but produce no evidence or
analysis.

> Until proven, one hypothesis with data to support
> postulating the hypothesis is as good as any other hypothesis with data to
> support postulating that hypothesis.

Note that there is NO data to support the LNTH. The "best data" (the
IARC study) has been conclusively shown to be a tortured effort
misrepresenting its own data, claimed eventually by the authors to be
only "not inconsistent with" the LNTH (which anyone could have concluded
before the effort started since the data is so poor and variable. Ethyl
Gilbert refused to claim that it supported the LNTH at the April NCRP
meeting, but that didn't stop Sinclair from saying she had demonstrated
the LNTH. Hundreds of studies that could show the LNTH, especially
medical practitioners and patients (enough people, with enough dose,
over long enough time) do NOT show the linear model (although some
studies *presume* the linear model to divide the high-dose effects by
the total dose to report linear effects/dose, contradicting thier own
data.)

> But, I think it hasn't been said frequently enough - we are debating the
> existence of a trivially small risk in a world filled with tremendously
> larger risks needing more immediate attention and a larger shared of our
> always limited resources.

Amen. But the LNTH is the basis to justify massive expenditures for
"trivial" risk, and will be defended to the limit of the bureaucratic
mission, and its mandate to its well-funded supporters.
 
> Bob Flood
> Stanford Linear Accelerator Center
> (415) 926-3793     bflood@slac.stanford.edu
> Unless otherwise noted, all opinions are mine alone.

Thanks.

Regards, Jim Muckerheide
jmuckerheide@delphi.com