Sorry Chuck.,
Retrospectively trying to control for confounding variables is useful
but does not remove all biases and the conclusions can be dead wrong.
Perhaps you remember the WHI--(Women's Health Initiative)which was a
randomized control trial (the gold standard study) and directly
contradicted many many smaller observational trials showing benefit of
HRT in women. All the myriad of previous observational studies of
hormone replacement tried to adjust for all known risk factors,
demographic variables, exercise ....... and
totally failed and indeed were dead wrong. That study had a major
impact on clinical practice.
Thus in medicine experiment trumps
observation for good reason. Observational data should be looked at as
hypothesis generating and with a jaundiced eye.
I made an egregious error of commenting on a medical issue and will not
do so again.
Perhaps we should agree to disagree and call it a wrap. Hand extended
electronically.......
Mike
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