Glad to know no-one else knows the answer to this (or if they do they're
keeping it to themselves).
I too have reservations about decision analysis and look forward to getting
a copy of Ubel PA, Loewenstein G. The role of decision analysis in informed
consent: choosing between intuition and systematicity. Soc Sci Med 1997
Mar;44(5):647-56 -which I just found -
in which the authors ...
".. point out that there is no gold standard for optimal decision making in
decisions that hinge on patient values. We also point out that in some such
situations it is too early to assume that the benefits of systematicity
outweigh the benefits of intuition. Research is needed to address the
question of which situations favor the use of intuitive approaches of
decision making and which call for a more systematic approach. "
Interestingly the whole thing has gone multi-dimensional with the work of
Charles and colleagues (also in the 18/9/99 BMJ) with their work on
patient's preferences for decision making style from physicians and John
Howie's enablement work..
If (and it is only if) the "most rational" choice comes from mathematical
decision analysis of EBM'ed data but patients are "most enabled" by shared
decision making with a physician they feel knows them ( but who, unless
superhuman or a list member, may be less adept at the maths or the EBM)
then an interesting trade off starts to appear.
Hmmmmm!
for a quick mind-stretch try PubMed with "decision analysis" and "patient
choice" Oh and get the systematic review by Bekker et al from the UK HTA
(free in uk and freely downloadable in PDF)
Cheers
Chris
Dr Chris Burton
a member of WestNet, the West of Scotland Primary Care Research Network
(actively planning research into just this sort of thing)
http://medicine.21.com/heartGP
----- Original Message -----
From: Guthrie, Dr Bruce <[log in to unmask]>
To: <[log in to unmask]>
Cc: <[log in to unmask]>
Sent: Thursday, September 23, 1999 10:54 AM
Subject: RE: deciding if decision analysis is good
> Dear Ben,
>
> Thank you. I like the distinctions you make, but I'm not sure where
> decision analysis as described in EBM fits in (= "clinical decision
> analysis"). It strikes me that "clinical decision analysis" is
> explicitly based on a normative model (rational choice theory -
> although I dislike the use of the word rational since it immediately
> implies that any other theory or method is irrational).
>
> However, as described in the EBM textbooks it is prescriptive - it is
> what we should do to make our decisions better, or at the very least
> what we should aspire to or should use when decisions get difficult.
> In that sense it is a decision aid within your definition. If you
> disagree with this, then you appear to be saying that we should
> judge that decision analysis is best because it's a neat theory.
> It's not amenable to test or evidence. This doesn't feel right to
> me.
>
> Deciding if it is any good could take two strands then. Firstly, do
> I agree with the axioms of the normative theory on which it is
> based? Secondly, even if I do then how would I assess that clinical
> decision analysis (CDA) helps people to make better choices? Before
> I could assess evidence for this, I think I need to be able to define
> what a "better choice" is and I'm not sure that I know how to do
> that.
>
> Any ideas?
>
> Bruce
>
> > Please don't confuse decision aids with decision analysis. The former
are
> > adjuncts, counseling aids "design to help people make specific and
> > deliberative choices" among different treatment options. The latter is
"is
> > an explicit, quantitative method of clinical decision making that
involves
> > SEPARATION of the probabilities of events from their relative values,
often
> > called utilities".
> > It is customary to think about three theories of decision-making: 1)
> > normative theory describes how (rational) people SHOULD (or ought to)
make
> > decisions, and is based on axiomatic mathematical or statistical
concepts
> > (usually, the best course of action is the one that maximizes expected
> > utility), 2) descriptive theory recognizes that people often violate
> > normative principles of decision making and is concerned with
understanding
> > HOW ("is vs. ought to") people actually make decisions, 3) prescriptive
> > theory deals with the question what should we do to IMPROVE our decision
> > making (such as developing decision aids).
> >
> > Normative models are evaluated by their theoretical adequacy, that
> > is, the degree to which they provide acceptable idealizations or
rational
> > choice.
> > Descriptive models are evaluated by their empirical validity, that
> > is, the extent to which they correspond to observed choices.
> > Prescriptive models are evaluated by their pragmatic values, that
> > is, by their ability to help people make better choices.
> >
> > Now, it is not clear at all how to define "gold standard" of
> > decision-making. People have argued about that for decades, and I am not
> > sure that there is any good consensus about it.
> >
> > Would be interesting to hear views of the members of this discussion
> > group.
> >
> > ben
>
> Bruce Guthrie,
> MRC Training Fellow in Health Services Research,
> Department of General Practice,
> University of Edinburgh,
> 20 West Richmond Street,
> Edinburgh EH8 9DX
> Tel 0131 650 9237
> e-mail [log in to unmask]
>
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