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Re: Cohen's erroneous statements
In response to Dr. Cohen's questions below.
1. There are numerous references concerning the glass-based detectors, for
example see:
Mahaffey JA, Parkhurst MA, Hui TE, Brownson RC, Alavanja MC., Factors
affecting use of CR-39 surface monitor technology to estimate past exposure
to indoor radon. J Expo Anal Environ Epidemiol. 6(4):425-37, 1996.
Field, R.W.. A Review of Residential Radon Case-Control Epidemiologic
Studies Performed in the United States. Reviews on Environmental Health.
16(3): 151-167, 2001
Field, R.W., Lynch, C.F, Steck, D.J.. Response to Alavanja et al. RE: The
Iowa Radon Lung Cancer Study
http://www.aje.oupjournals.org/cgi/content/full/152/9/895). American Journal
of Epidemiology. 151(11): 895-896, 01 Nov 2000
Field RW, Steck DJ, Parkhurst MA, Mahaffey JA, Alavanja MC. Intercomparison
of retrospective radon detectors. Environmental Health Perspectives.
107(11): 905-10, Nov 1999
Steck, D.J., Field, R.W.. The use of track registration detectors to
reconstruct contemporary and historical airborne radon (222Rn) and radon
PROGENY concentrations for a radon-lung cancer epidemiologic study.
Radiation Measurements. 31: 401-406, 1999
http://www.csbsju.edu/MNradon/retrospective_radon.htm
http://www.csbsju.edu/MNradon/radon_epidemiology.htm
http://www.csbsju.edu/MNradon/projects/researchprojects.html
2. Many of the case-control studies coolected information on ETS.
The studies used pack years smoked by other people (other than the subject)
in the home and they also asked how many people in the home smoked over the
30 year period. This information was used in the multivariate analyses if
the impact was stistically significant.
3. Field's Radsafe posting of March 9, 2000
Dr. Cohen,
As time permits, I would be very happy to work on a joint paper with you to
discuss how these factors are taken into account in a case-control studies
versus ecologic studies. Let me know if you are interested. The paper below
touches on how these questions are addressed in a case-control study.
Field, R.W., Steck, D.J., Lynch, C.F., Brus, C.P., Neuberger, J.S., Kross,
B.C., Residential Radon-222 Exposure and Lung Cancer: Exposure Assessment
Methodology. Journal of Exposure Analysis and Environmental Epidemiology,
6(2): 181-195, 1996.
----------------------------
Cohen subsequently indicated he was not interested.
I would find a paper on this helpful especially since you keep comparing
your ecologic studies to the case-control studies. In the arhives you said
you can not use an ecologic study to assess the risk posed by radon
exposure. It appears you have reversed your position.
Sincerely, Don Smith
------------------------------------------
>From: BERNARD L COHEN <blc+@pitt.edu>
>To: Rad health <healthrad@hotmail.com>
>CC: info@eic.nu, radsafe@list.vanderbilt.edu
>Subject: Re: Cohen's erroneous statements
>Date: Fri, 11 Jan 2002 15:25:53 -0500 (EST)
>
>
>On Fri, 11 Jan 2002, Rad health wrote:
>
> > BERNARD L COHEN wrote on Fri, 11 Jan 2002 09:40:36 -0500 (EST)wrote:
> >
> > BC Note that your suggestion would also affect every other study that
> > has ever been done on radon vs lung cancer, including all the
>case-control
> > studies.
> >
> > Dr. Cohen's statement is incorrect - The MO study used glass-based
>detectors
> > which can estimate past radon progeny exposure. Further- the Iowa study
>used
> > HRD detectors which can examine the degree of progeny attachment and
> > retrospective radon progeny exposure
>
> --Can you remind me of the references where these detectors are
>described? I will look them up, but I seriously doubt if they truly handle
>the problem of equilibrium factors and unattached fraction. In any case, I
>am confident that my remark applies to all the other case-control studies.
>
> > BC Are you suggesting that a treatment is needed for non-smokers
> > living in houses where there are smokers? That would be very difficult
>in
> > any study. In case-control studies, they don't ask whether there are
>other
> > people in the house who smoked.
> >
> > Again Dr. Cohen's statement is absolutely false. Most of the
>case-control
> > studies collect this information including the IA and MO studies.
>
> --What do they do with that information? I don't see how they can
>use it. Please explain.
>
> > Dr. Field offered to write a paper with Dr. Cohen over a year ago to
>examine
> > the strengths and limitations of the ecologic approach versus the
> > case-control approach in evaluating the risk posed by residential radon
> > exposure. Dr. Cohen declined (check the archives).
>
> --I don't remember this; please let me know how to check on it. In
>any case, I am not a defender of ecological studies in general; in fact I
>have offered to show how any other published ecological study can give a
>false conclusion. However, I have not been able to do that for my study,
>and neither has anyone else. My study is very different from all other
>ecological studies in that I am testing the linear-no threshold prediction
>rather than trying to determine the risk vs dose relationship for
>individuals, and also in that I have so many data points (1601 counties)
>that I can treat confounding factors with stratification; other
>differences are discussed in my papers.
> I have never dodged any attempt to explain my data, if that is
>what you are implying.
>
> Dr. Cohen should be
> > able to support the validity of his findings without relying on saying
>this
> > is how case-control studies do it. In other words let your study stand
>or
> > fall on its own merits.
> >
> --If people accept the case-control studies and I treat some
>problem the same way they do, I think they should not criticize me on that
>aspect. I never rely on that as my only defense, but simply mention it in
>passing.
>
>
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