RE: Cohen's Ecologic Studies

[BERNARD L COHEN <blc+@PITT.EDU>]

On Mon, 3 Jun 2002 EPIRAD@mchsi.com wrote:



> The bottom line as I have been trying to get across in

> HP publications for years is that smoking is not a

> linear function within or across counties in the United

> States.  If it were, then you could possibly adjust for

> it better at the ecologic level.



	--My several independent treatments of smoking make no assumptions

about smoking being a linear function of anything



 As for Dr. Cohen's

> ecologic analyses, he can account for only about 30% of

> the lung cancer mortality with his smoking data.



	--Wrong, wrong, wrong. The fact that R-squared is only 30% derives

from the small up and down statistical variations. The true indication of

predictability is the standard deviation of the slope of the regression of

lung cancer on smoking prevalence which is very small percentage-wise



 Cohen's

> derived LNTT formula does not have the ability to adjust

> for non-linear covariates like the BEIR VI formula

> does.



	--Wrong, wrong, wrong. My treatments of confounding factors do not

depend on linearity. My treatment was based on BEIR-IV as it was the

latest thing available. I could do a treatment based on BEIR-VI if it

would be publishable, but I doubt if it would be considered new enough to

be published





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