Re: Medical Research-Evidence


"Herman Rubin" <hrubin@xxxxxxxxxxxxxxxxxxxx> wrote in message
news:e5fj3d$2udi@xxxxxxxxxxxxxxxxxxxxxxx
In article <k4Eeg.6437$921.356@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
George Conklin <georgeconklin1@xxxxxxxxxxxxx> wrote:

"Skeptic" <bcs002b@xxxxxxxxx> wrote in message
news:cikag.733050$084.383622@xxxxxxxxxxxx

[Long line of back-and-forth deleted.]



Even if the results get no better than they are now, their is
a
signficant
difference, clincally and statistically.

What Herman was trying to tell you is that this is not so.

Herman is not a a doctor and a physician is in a better situation
to
determine what is CLINICALLY significant.

On that, I agree, provided that the full information
is known. One can have either type of significance
without the other. Unfortunately, too many medical
people do not realize this.

....................

Herman's comment that he would rather go with a study where 3 out
of
3
are cured than with a large study showing very small differences. It
is
a
valid point. He is in favor a Bayesian methods. Even the New York
Times
had an article comparing the approaches.

I'm not disagreeing, which you don't seem to understand. However, we
don't
have such results. What we have is a larger study showing a smaller
response, but nonetheless, it showed that patients were cured from
surgical
intervention for prostate cancer. Small numbers? Yes. But lives are
lives
so meaningful numbers.



Very small
differences must be evaluated carefully even if statistically
significant.
The original authors state differences are small. Why dispute
them?

I'm not disputing them. I support them. You just don't seem to
understand
that a relatively small difference can be a very important
one...
especially if you're amonge the extra 20 lives saved in that
study.

The problem is that when you rerun the study, with low levels
of
significance you might just as well find the opposite, as the HRT
studies
showed or seemed to show.

you're living in hypotheticals now. Fact - the study showed a
survival
advantage for surgery vs. watchful waiting. It's the best study we
have
right on that topic.

Actually according to what Herman has posted over the years, it is
not
hypothetical at all, but a possible artifact.

Yes, an unlikely possibiltiy, but nonetheless a possibility. This is
why
multiple studies are being done and why the same study in question will
continue to evaluate their results over the years. The quality of the
study
from this one study was excellent and I find the results believable.
If
held true over time and confirmed by other studies, the issue will have
no
doubt left. The doubt at this time is minimal.



Here is a comment from UK:

Prostate therapy benefits doubted
Many men diagnosed with low-grade prostate cancer do not benefit from
radical treatment, research suggests.
The researchers calculated that, even without treatment, only about 1% of
men aged 55-59 with diagnosed low-grade disease would die within 15
years.

This is NOT a small number. What are the other factors
involved? We need to find more of the relevant factors,
and this is not going to be done by the type of medical
studies now being done. We cannot look at one or two
things at a time, but must look at dozens.


Correct, but that is not how the 'gold standard' works Herman. What the
study also said was that there seems to be little evidence that the 1% would
be less than 1% if aggressive methods were used. In fact, it could be MORE
than 1%.


This is the opposite problem to the usual data mining.
It is hard to come to valid conclusions in high dimensional
problems without making assumptions, and few realize what
is involved in making probability assumptions. As one of
the too few who have looked into the problem of how much
one can get, there are things which can be done, and things
which cannot.

Side effects of radical treatment such as surgery and radiotherapy can
include incontinence and impotence.

This involves both probabilistic considerations and
considerations of personal utility.

It also requires the use of idiosyncratic variables.
Population figures are inadequate; they only look at
the type of cancer, not who has it. It is possible
to estimate probabilities without observing "identical"
cases, and the medical profession, as well as others,
needs to realize this and act on it.


Actually most of the real variables remain hidden because the basic
science is still not there.

The Department of Health said its advisers would consider the Institute
of
Cancer Research findings.

The study appears in the British Journal of Cancer.


The decision whether to have radical treatment can be tremendously
difficult for the patient
Dr Chris Parker

Of course. The information made available to the
patient is inadequate.

[Large quoted section delete.]

There are also cultural variables. The American idea of 'cut it out'
rules right now, but I am not sure it does in UK.


.

Relevant Pages

  • Re: Spiritual Healing Lectures
    ... The probability that if you get a cold, ... Thus, the statement that "healing often happens" is meaningless, since ... or *faster* than healing without his magic treatment. ... with neither the indivdiual patient nor the person judging ...
    (misc.health.alternative)
  • Re: Test
    ... What is the probability that a patient will look exactly ... Maybe Neil Brooks is correct. ... His patient Neil Brooks ... are you still sure that I'm David Granet, ...
    (sci.med.vision)
  • Re: New telephony product based on RIJNDAEL and Random Padding
    ... > There's an argument that a 128-bit block is inadequate. ... Changing keys every month, and assuming continuous ... For small x, 1 - exp~ x, so the collision ... probability in this case is about 2^or about 5e-23 per month. ...
    (sci.crypt)
  • Re: Difference between P(a|b) and P(b|a)
    ... There is a chance that the shot will miss due to imperfect design. ... And Pis the probability that if it will take the dose at the time given that patient will be cured. ...
    (sci.math)