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Iowa Radon Lung Cancer Study
Dr. Long,
Is there a reason you continue to send me these emails? Do you have a
question I can answer? It is my impression from your emails that you fail
to understand the basics of the various epidemiologic study designs.
The Iowa Study and supporting studies were peer reviewed. The major findings
paper, that was accepted by the prestigious journal AJE, was peer reviewed
by three outside reviewers. They highly recommended the paper for
acceptance. Among the authors of the Iowa Study were very qualified
biostatisticians and epidemiologists. For example, see:
http://www.public-health.uiowa.edu/faculty/~woolson.html,
http://www.public-health.uiowa.edu/faculty/~lynch.html, etc. Other
http://www.public-health.uiowa.edu/news/2001_archive/201radon.html studies
are currently underway:
If you have specific criticisms of the paper, please feel free to write a
letter-to-the-editor.
Bill Field
----- Original Message -----
From: <hflong@postoffice.pacbell.net>
To: field <bill-field@uiowa.edu>; <rosalyn@ioip.com>;
<michael.g.stabin@vanderbilt.edu>; <blc+@pitt.edu>
Sent: Wednesday, January 09, 2002 3:08 PM
Subject: Iowa Controls - Not Matched
Howard Long MD MPH, Family Doctor and Epidemiologist
363 St. Mary St., Pleasanton CA, 94566
(925) 846-4411, Fax 4524, Page 787-0253 hflong@pacbell.net
Dear Professor Field,
I have great respect for your scientific honor and the quality of the
Iowa study.
I am happy that you write, "I AM NOT A DEFENDER OF THE LNT THEORY".
When opposite inferences are reasonable from similar studies, like your
Iowa study and the N Shipyard Worker Study (also case control and 10 x
as large as yours), I believe an experiment is needed.
First, even if a drug company were to fund 100 clinical trials,
(prospective and double blind) with N in each such that some trials
would likely show p<.05 of chance results,but publish only studies
showing benefit, would it show the medicine effective?
You studied the one location in 100 (Iowa women) having no negative
correlation of radon and lung cancer mortality, in Cohen's study - 200 x
as large, albeit ecologic.
.
Second, in Topics Under Debate, Radiation Protection Dosimetry V95,1,p77
you write in Rebuttal, "The participants' smoking histories do not need
to match the smoking histories of the controls since the effect of
smoking can be adjusted for using standard statistical methods." This
follows Klaus Becker's Argument that "- in the Iowa Lung Cancer Study by
Field et al 86% of the ling cancer cases were smokers, but only 32% of
the controls." Ibid, p79. Our Professor of statistics at UCB PH, Bill
Gaffney, would often remind us,
"Know your assumptions!" In your study, the controls are not matched. I
do not believe that here, "smoking can be adjusted for using standard
statistical methods".
I, unlike some cynical colleagues, believe that your intent, like mine,
is to prevent lung cancer and advance science. I have in the past
rationalized projects (like a method of colon cancer detection) more
than I believe you have rationalized this power of statistics to correct
for the difficulty in finding controls that match for smoking. I hope
you will come to believe, as I do, that less smoking by controls may
have been the reason they had less cancer, rather than the less radon.
With continued respect and best wishes
Howard Long