Steve, I actually very much agree with the sentiments expressed in your e-mail. One important additional issue is how we as humans are wired to react toward false positives vs. false-negatives. In one our papers that deals with the issue with inferences in setting of inconclusive data (Seminars in hematology 2008;45(3):150-9) we also made the following point: "It is important to note that our tolerance toward making mistakes with respect to benefits and harms may dramatically differ. That is, we act differently when it comes to the possibility of wrongly concluding that intervention is harmful (when in fact it is not) than falsely concluding that treatment is beneficial (when in fact it is not). It appears that humans are cognitively more ready to wrongly accept the signal of potential benefits than the one that carries the potential of harm....when it comes to benefits, we accept more false-negatives (typically set at 1-beta=0.2  )  than false-positive signals (typically set at alpha=0.05 ), indicating that before we recommend treatment to everyone we require a higher level of certainty that the intervention is in fact beneficial. However, when it comes to harms, we accept more false positive than false negatives evidentiary signals out of a desire to minimize missing a dangerous signal, which seems to be evolutionarily wired in human cognition."
best
ben

________________________________________
From: Evidence based health (EBH) [[log in to unmask]] On Behalf Of Steve Simon, P.Mean Consulting [[log in to unmask]]
Sent: Wednesday, September 16, 2009 3:15 PM
To: [log in to unmask]
Subject: Re: cost-effectiveness and health reform

Dr. Carlos Cuello wrote:

> Interesting reading this survey from Mayo published in the NEJM; over
> half of physicians reported a moral objection to using
> cost-effectiveness analysis data.
>
> http://bit.ly/10kx4Q
>
> complete link: http://healthcarereform.nejm.org/?p=1785
>
>
> Any comments?

I'm not an expert on healthcare reform and I'm not a doctor, but I'll
comment anyway. I've decided that all of life's controversies can be
related to sensitivity and specificity. Bear with me here.

You can define sensitivity in terms of a formal diagnostic test, but I
prefer to think of it in more general terms: sensitivity is one minus
the false negative rate and specificity is one minus the false positive
rate.

The problem with most of life's controversies is that half the people
"too sensitive". They are arguing about how awful all the false
negatives are and ignore the false positives completely.

The other half, of course, are "too specific". They argue about all the
false positives and ignore the false negatives completely.

An example of the "too sensitive" group is those folks who advocate
greater cancer screening with anecdotes of "I didn't get screened and
now I'm going to die unnecessarily" (false negative) or the flip side of
the same coin: "I got the screening test and it saved my life." Now I
don't want to be too harsh, as greater cancer screening is often a good
thing, but where is the balance of discussion of the unneeded biopsies,
the unnecessary anxiety, etc. when a false positive result occurs?

This applies to other areas as well. There are people who argue that the
  U.S. Food and Drug Administration (FDA) has been making it too
difficult and too expensive for drugs to get tested and approved. These
are the "too sensitive" people, who worry about false negatives (good
drugs that are kept off the market). Others argue that the FDA is too
beholden to industry and needs to tighten up their rules. These are the
"too specific" people who worry about false positives (useless drugs
getting approval).

Tort reform falls in the same category. The critics of the U.S. legal
system for malpractice claims are "too specific" because they worry
about the false positive cases like the woman who spilled coffee in her
lap while driving and sued McDonald's. Yet any effort to make it more
difficult to sue and prevail in our court system is almost certainly
going to increase the false negative rate, those people who were truly
harmed by the negligence of an individual or corporation and are unable
to seek adequate compensation. Of course, the "too sensitive" groups
will highlight all those evil corporations and look at how they are
getting off without having to pay a serious penalty for their wicked
deeds (false negatives).

A false positive in healthcare is a patient that is needlessly treated.
A false negative in healthcare is a patient that misses out on a helpful
treatment. It seems to me that cost effectiveness research is a careful
attempt to balance the costs of false positives and false negatives and
their respective probabilities.

The big problem, though, is that the parties that bear the bulk of the
cost of a false positive are usually the insurance companies and the
parties that bear the bulk of the cost of a false negative are the
individual patients. Although I do realize that higher insurance costs
will eventually back to me, I tend to discount that if I am an
individual patient with the prospect of a serious disease staring me in
the face.

That's why there are no easy answers. Consider prophylactic treatment
with antibiotics. If you treat a patient with a viral infection
unnecessarily with antibiotics, who pays the cost? The patient does to
some extent because of the exposure to unnecessary side effects of the
antibiotics, but the greater cost is to society in general, as
antiobiotic resistant organisms gain a more solid foothold in our
community. Society doesn't pay as much of a price if a bacterial
infection is left untreated--I'm the one who was to miss work and suffer
the misery of an infection that could have been cleared up a whole lot
sooner with a few pills. I suppose society suffers in some sense that I
won't be able to compose long emails like this when I'm sick, but
somehow I think that society will survive with one less rabid emailer.

Should we close a school when a report of an H1N1 infection appears?
There's a cost to society when H1N1 spreads quickly, but there is a cost
to the individual parents when they have to miss work or pay a
babysitter for their kids because they don't have a school to go to
during the work week.

In the broad sense, society suffers when an individual suffers and an
individual suffers when society suffers. But it's hard to take the broad
perspective when it's your body on the line.

So I'm all in favor of cost-effectiveness research, partly because the
research demands the use of lots of complicated statistics. Seriously,
cost effectiveness research avoid the trap of the "false positive"
anecdotes dueling with the "false negative" anecdotes, and it tries to
avoid being "too sensitive" or "too specific". But as long as there is a
disparity in who pays which bills, I can understand why cost
effectiveness research is controversial.
--
Steve Simon, Standard Disclaimer
Free statistics webinar, Wed, Oct 14, 10am CDT.
"P-values, confidence intervals, and the Bayesian alternative"
Details at www.pmean.com/webinars