Paul Jones <[EMAIL PROTECTED]> wrote in message
news:<[EMAIL PROTECTED]>...
> <snip>
>
> So the research says that of a large number of people who
> had heart attacks at a centre, 124 people had used MJ in the
> year preceding the HA. Of these 9 reported that they had
> used MJ in the hour preceding the HA. All MJ users were
> questioned on the frequency with which they used MJ. The
> relative risk was reported as 4.8 - I used this to
> back-calculate that the average number of MJ usages per year
> rounded 141 -> (9/n)/(115/(8760-n)) = 4.8
<snip>
ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°
Surely this whole research is based upon a false premise. Isn't it
like saying that 90%, say, of heroin users previously used soft drugs.
Therefore, soft-drug use usually leads to hard-drug use - which does
not logically follow. (A => B =/= B => A)
Conclusions drawn from the set of people who have had heart attacks
cannot be validly applied to the set of people who smoke dope.
Rather than collect data from a large number of people who had heart
attacks and look for a backward link, they should monitor a large
number of people who smoke dope. But, of course this is much more
expensive.
Just my humble tupennyworth,
Eamon
ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°`°º¤ø,¸¸,ø¤º°
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