> I really disagree with the notion that correlation strongly suggests
> causation. IMO this is one of the major pitfalls of dealing with
> statistics. We /know/ (we =3D you + me + many others :) that there are
> correlations that are not caused by a causal relationship, so a
> correlation doesn't suggest anything -- unless there is something else
> that shows that the correlation is in fact caused by a causal
> relationship.

Causation causes correlation.
Correlation thus suggests in a given case that causation may be at work.
Increasing degrees of correlation increase the statistical probability
that causation is at work.

If you get small clusters aka families, that by themselves are
statistically too small to demonstrate a high probability of
causation, enough such groups that either have high incidence or low
incidence of a given disease, increase the chance that there is a
causative agent at work. Or "if heart disease can be observed to "run
in families" in a significant percentage of cases, then the existence
of a causal element at the family level is suggested". eg - made up
example, if 40% of the populace die of heart attacks then, if in 5% of
families, 80%+ of people die of heart attacks,  then there is a strong
indication that there is a family level causative factor in these
cases. This does not HAVE to be genetic.

> Still... the fact is that even if there was something genetic, you can't
> change it. "I pray for the serenity to accept the things I cannot
> change, the courage to change the things I can, and the wisdom to know
> the difference" is not only for alcoholics :)

BUT, you make my point exactly. This study CLAIMS that in this context
there are, apart from a few specific and well known exceptions,
essentially NO things you can't change - THEY are, literally, claiming
that a high % of family deaths aged in the  mid 70's due to heart
attacks is NOT an indicator that other family members may be
genetically predisposed to heart disease.
IF this was true it would be stunning for me - it would mean that I
should be able with due care and action to "probably" have a healthy
outcome far different than my typical  family history - rather than
just possibly.


> So for any individual who
> thinks he might possibly be affected by the genetics, the course of
> (immediate and life-saving) action is /not/ in the genetics, not even in
> understanding it -- it is in the things he or she can change. Which
> again are the lifestyle patterns.

Yes - and if there ARE NO genetic effects, as they claim, then
lifestyle could make a vast difference.

I've just found out that the strange and until now apparently
irrelevant condition that I have - "Gilberts syndrome" - allegedly
decreases my risk of heart disease by typically a factor of 3. That,
plus the claims of that paper, if true,  would make a significant
different to my life "expectancy" - as opposed to my actual life span.
 Odds are, therefore, that I'll die any day now :-).


       Russell
--=20
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