I'm get tired of it too, but...

[Vincent.King@DOEGJPO.COM (Vincent King)]

     Dear group,
     
     Can someone make the radon/lung cancer issues here a little simpler 
     so the average HP can understand them?
     
     A linear, no threshold theory is a straight line going through 
     zero.  Only the slope is a variable.  And, at the exposure levels 
     we're discussing, it doesn't matter how you spread the exposure out 
     in a group (if risk is truly proportional to dose in a linear 
     manner). Anything else is not LNT.
     
     Since it seems to be a given that the number one cause of lung 
     cancer is smoking, if you can do a reasonable job of adjusting for 
     smoking, you MIGHT be able to see other lung cancer cause/effect 
     relationships if they are 'big' enough. (If you can't properly 
     adjust for smoking, it will overwhelm any other effects you're 
     looking for).
     
     The SECOND leading cause of lung cancer is (according to assertions 
     by the EPA) radon. IF this is true (and if you can properly adjust 
     for smoking as stated above), then looking at average radon 
     exposures and lung cancer rates in similar populations should 
     either show (1) a positive correlation or (2) nothing but random 
     scatter if the effect is too small to see.  It should NOT 
     consistently show you a negative correlation, regardless of 
     'confounding' influences (which, by the definition at the top of 
     this paragraph, must be smaller than the number two cause of lung 
     cancer, and which would have no reason to 'join forces' and 
     confound in the same direction.)
     
     Turning the last sentence around, if you DO see a negative 
     correlation between radon exposures and lung cancer rates, you can 
     say either (1) the negative correlation is due to the radon 
     exposure (which would be suggestive of hormesis) or (2) the 
     negative correlation is due to something other than radon (which 
     implies that radon exposure should be much further down the list 
     than the 'Number two cause of lung cancer'. Notice that this ALSO 
     implies that the currently accepted LNT regarding radon is wrong, 
     if it can be overwhelmed so easily by 'something else'). 
     
     If you misinterpret confounding factors, you shouldn't get a 
     negative correlation - you should get 'noise'.  For example, I 
     suppose you can take issue with whether average radon 
     concentrations in a county are truly representative of average lung 
     exposures, but how likely is it that average radon concentrations 
     in a county are REVERSED from average individual exposures?
     
     What Dr. Cohen seems to be saying (and please correct me if I am 
     wrong, Dr. Cohen) is simply that the relationship between county 
     radon concentrations and lung cancer rates is the opposite of what 
     you would expect if the current LNT regarding radon is true. He 
     does not say that the cancer rates are 'caused' by anything. The 
     arguements against this conclusion, while they may also be valid, 
     have been far too obscure for me to follow. 
     
     I do not fancy myself to be an epidemiologist, but I have been 
     exposed to some of the basic concepts, so, IN RELATIVELY SIMPLE 
     TERMS PLEASE, is my understanding right or wrong, and if wrong, why 
     is it wrong?  (And if it is wrong, we'd better look at HP education 
     in this country, because I base my thinking on what I thought the 
     HP education process was trying to impart.)
     
     Thanks,
     
     Vincent King
     vincent.king@doegjpo.com
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