Hi
As a health economist who is now involved in developing 
clinical trial design I am very interested in this debate. 
With regard to the point about health economists' suspicion 
of EBM, I personally favour its use in cost-effectiveness 
calculations. However, there are caveats that must be borne 
in mind (and which may explain any apparent suspicions held 
by health economists):
1. As already alluded to, there is no universal 
cost-effectiveness ratio for any given treatment: costs 
vary enormously between setting (geographical and 
clinical). Given this variability in the numerator of this 
ratio, health economists are (or should be) wary of using 
some standard effectiveness figure for the denominator 
unless they are confident about its applicability to the 
particular setting under consideration. Local priority 
setting (I'm not afraid to say rationing either) by Primary 
care groups will make this more of an issue.
2. The variability of the denominator, the difference in 
effectiveness between the two treatments being compared, is 
often greater than imagined. This difference depends upon 
the underlying prevalence figures and, like the NNT, 
exhibits much greater variability than, say, the relative 
risk. (Or putting it another way, the proportionate effect 
of a treatment tends to be more stable over different 
patient groups than the absolute effect; 
cost-effectiveness ratios use absolute effects).

Therefore I would agree with DS in that local NNTs should 
be used, where possible, for local priority setting. We are 
in danger of repeating the media circus of undertaking 
ineffective treatments (or in this case cost-ineffective 
treatments) if accurate cost figures are accompanied by 
clinical data that is irrelevant to a particular setting or 
just plain wrong.

cheers
terry
********************************************
Terry Flynn
MRC PhD Student
Department of Social Medicine 
University of Bristol
Canynge Hall
Whiteladies Road
Bristol BS8 2PR

Tel: 0117 928 7375
E-mail: [log in to unmask]
********************************************

On Wed, 10 Mar 1999 19:18:50 +0000 "Toby Lipman 7, 
Collingwood Terrace, Jesmond, Newcastle upon Tyne. Tel 
0191-2811060 (home), 0191-2869178 (surgery)" 
<[log in to unmask]> wrote:

> In message <Pine.WNT.3.96.990310152439.-1038313D-
> [log in to unmask]>, Dave Sackett <[log in to unmask]>
> writes
> >grand discussion; thanks.
> >
> >after working in the US, canadian, and UK health care systems, i've asked
> >(but not answered!) 2 questions about NNTs and health policy: 
> >
> >1. didn't rationing begin as soon as the first stone age shaman trephined
> >the skull of the first schizophrenic in an attempt to let out the bad
> >spirits (surely there were lots more schizophrenics than flint trephines
> >or shamans), and haven't we been rationing ever since? 
> >
> >2. if rationing decisions are made democratically and at a local level,
> >don't variations in disease frequency and severity force NNTs to vary from
> >place to place, and shouldn't (indeed, mustn't) there be differential
> >"health care by postal code" on this basis, even when other elements of
> >the decision (eg, values and preferences) are similar?
> >
> >erudite answers to these naive questions would be appreciated (but not
> >necessarily understood). 
> >
> >cheers,
> >dls
> 
> As usual you ask the right questions but if you're sensitive, don't read
> on! I've become interested in the health economists' view of these
> matters. They make the point that rationing is inevitable because all
> resources, including health care, are "scarce" (by which they mean
> finite - although how finite depends on choices made by individuals and
> governments). If resources are scarce, then they need to be allocated
> efficiently and equitably (and economists have developed various methods
> of economic evaluation which, although far from perfect, at least
> clarify the issues and to some extent quantify the choices).
> 
> Gavin Mooney (Economics, Medicine and Health Care 2nd ed, chap 8, 1992,
> Harvester, Wheatsheaf) writes about the ethical dimension of these
> choices and suggests (like other economists) that justice and equity in
> health care are interdependent with ethics and efficiency. So not taking
> efficiency into account leads to inequity because every time you choose
> a clinical intervention you incur an opportunity cost, and if you choose
> inefficiently, the excessive opportunity cost deprives some other
> patient of a potentially useful intervention. 
> 
> Mooney argues that this is unethical, but that medical ethics, from the
> time of Hippocrates, considers "virtue" and "duty" paramount, not the
> "common good". Thus if we adhere to medical ethics, we place "virtue"
> and "duty" (to the interests of each individual patient) above the
> "common good" (society as a whole - all the other potential patients).
> The GMC says that British doctors should take the NHS's limited
> resources into account but that this is subordinate to the interests of
> individual patients! This is illogical - if we are to allocate resources
> efficiently and equitably, we must balance the interests of the patient
> we are dealing with against the common good - and looking after the
> common good is in the interests of the majority of patients.
> 
> I'd guess a lot of us do this but feel uncomfortable with it, while
> other doctors bury their heads in the sand and bluster about "clinical
> freedom". Our problem is compounded by the unwillingness of politicians
> to be explicit about the choices that need to be made. Economists seem
> to get a bit hot under the collar about the way doctors behave and
> categorise us as "romantic" (we plough on regardless and behave as
> though there were limitless resources) or "monotechnic" (we want to do
> as many CABGs as possible, because that's what we're good at and like
> doing). 
> 
> There is also the issue of the patient's duty to society but maybe
> that's another discussion (for example a patient who insists on a GP
> home visit for a sore throat instead of attending the surgery or, better
> still, taking some aspirin and not contacting a doctor at all, causes an
> opportunity cost to the practice and deprives other patients of GP
> time).
> 
> I've never understood why there seems to be such suspicion of EBM among
> economists (perhaps they think we are both romantic and monotechnic!).
> It seems to me that questioning, appraising evidence, using information
> like NNTs leads us to at least consider both the effectiveness and
> efficiency of what we do. But probably we also need to look at the
> health economics viewpoint in more detail as it does offer useful
> insights. (thinks: should we offer sessions on it at EBP workshops?)
> 
> Toby
> -- 
> Toby Lipman 7, Collingwood Terrace, Jesmond, Newcastle upon Tyne. Tel 
> 0191-2811060 (home), 0191-2437000 (surgery)





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