[ RadSafe ] Incidence vs death question, was: Exposed " -had lower incidences of all cancers - "

[John Jacobus]

Keith,
Issues concerning the Navy nuclear shipyard study come
up periocially.  Maybe yearly?  You may want to check
the RadSafe achives.

The primary flaw with the study is that the cohort,
unexposed shipyard workers may not have been as
healthy as members of the general population.  This
may be due to asbestos exposures. 

Of course, some still quote the "favorable" aspects
while ignoring the question as to whether or not it is
even a valid study.

--- Keith Welch <welch at jlab.org> wrote:

> Folks,
> I am not an epidemiologist and have no experience in
> that field.  But 
> recently, partly due to the posts here, I have been
> wondering about 
> this.  Maybe I just haven't thought it through well
> enough.  It seems on 
> its face that using cancer incidence rates would be
> preferable to 
> mortality, due in part to the issue of changes over
> time in cure rates, 
> but also because it would seem to help correct for
> the healthy worker 
> effect (incidence rate is not as affected by the
> availability of health 
> insurance or treatment as mortality rate) - and
> possibly the "rich 
> victim effect", which I have not heard many people
> talk about, but 
> assume must be confounding; the difference in cure
> rates in different 
> socio-economic classes.  I would suppose that could
> probably be dealt 
> with by careful cohort selection.  At any rate, I've
> heard that the 
> shipyard worker study was flawed due to the
> following: (1) screening for 
> nuclear workers at the shipyards disqualified people
> with family history 
> of cancer, and (2) removal of people from nuclear
> worker status (and 
> therefore, presumably from candidacy for the study?)
> in the event they 
> were diagnosed with cancer during employment.  Are
> either of these based 
> in fact?
> 


+++++++++++++++++++
“We must face the fact that the United States is neither omnipotent or omniscient — that we are only 6 percent of the world’s population; that we cannot impose our will upon the other 94 percent of mankind; that we cannot right every wrong or reverse each adversity; and therefore there cannot be an American solution to every world problem.”
-- John F. Kennedy 

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


 
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