OK OK - as a positivistic clinical pragmatist looking for foreground
answers
assuming there is no 'truth' except that one is alive or dead what is
the 'best available' to me.
Best - for me means, taking into account the health care context, the
highest level of evidence http://www.cebm.net/levels_of_evidence.asp
balanced against the most recent evidence.
Available - is that you are able to access it within the appropriate
time frame for that health care situation - that might mean seconds for
a drug dose in ER.
Within that time frame there is also is the consideration of whether the
evidence is appraised or non appraised. There is no point giving full
text on line Medline to a GP during his clinic. However Clinical
Evidence or evidence based medicine may be valuable.
However the health care context is KEY - the patient who says that the
pain was relieved by a tablet is far more important than the trial that
says the tablet is not the most effective. The balance and discussion of
the two options with the patient is the really interesting part. They
know one drug works (maybe with side effects) and there is another that
evidence suggests is better (more pain relief). But they have already
benefited from the former.........................
Martin
-------------------------------------
Chair Family Medicine
McGill University
515-517 Pine Avenue West
Montreal
H2W 1S4
Tel 514 398 7375
Fax 514 398 4202
-----Original Message-----
From: Ted Harding [mailto:[log in to unmask]]
Sent: Thursday, September 18, 2003 11:40 AM
To: [log in to unmask]
Subject: Re: evidence for evidence based practice
On 18-Sep-03 Ian Bowns wrote:
> In article <200309170959256.SM00281@IM02>, Roy Poses
> <[log in to unmask]> writes
>>But how would you judge what evidence is the "best available?" Why try
>>to find the best available evidence unless best available means most
>>likely to reflect the truth?
>
> Forgive me, but I cannot resist commenting. The example cited of
> quantum mechanics and Newtonian seems apt to me. As Popper suggested
> (in 'The Logic of Scientific Discovery'), I think that science
> progresses by falsification of hypotheses, not their verification. We
> improve on the breadth to which the available theories are applicable
> by finding their limits through falsification. I see many theories we
> have not (yet) falsified, but am not sure that any will stand forever.
And forgive me but I cannot help going further down this side-path!
The statement "I think that science progresses by falsification of
hypotheses, not their verification." is, I think, incomplete. Better and
more accurate, it seems to me:
"Science progresses by falsification of hypotheses, not their
verification, and putting something better in their place."
Mere falsification simply destroys something which may nevertheless be
very useful in its own right, as indeed Newtonian mechanics was (and
still
is). NASA scientists still use it for motion of objects in space, even
though it is "false" and has been replaced by Relativity. Ths point
there
is that it is _adequate_ for many purposes, even if "false". Popper's
main point, of course, was that, according to his view of science,
verification (of truth, rather than adequacy) is simply not possible.
So falsification of Newtonian dynamics (which had already come close to
happening in the 19th century when the anomalous precession of Mercury
was established, together with the realisation that Maxwell's
electromagnetic theory was non-Newtonian) would have been a regression
in science if it had led to people avoiding its use even where it was
adequate. Putting Relativity in its place was the advance; and then it
became apparent just _why_ Newtonian mechanics is adequate, because the
amount of error involved in its use can be calculated theoretically and
can be seen to be negligible for most purposes (including the more
extreme
purposes of putting objects into space). [And the springboard for
Relativity was following the logical consequences of "If Maxwell is
incompatible with Newton, then let Maxwell win, even if this is not
compatible with our normal concepts of space and time".]
Of course, in the 20th-century applications of atomic physics Newton
was clearly inadequate, but that is another story ...
Best wishes to all,
Ted.
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E-Mail: (Ted Harding) <[log in to unmask]>
Fax-to-email: +44 (0)870 167 1972
Date: 18-Sep-03 Time: 16:39:33
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