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This is a bit puzzling. Uncertainty should imply ELIGIBILITY, and not other
way around.
bd

-----Original Message-----
From: Anne Leigh Brown [mailto:[log in to unmask]]
Sent: Monday, August 20, 2001 4:37 AM
To: [log in to unmask]
Subject: Re: FW: uncertainty principle


Dear Jeanne
I see that your example of the uncertainty principle is from the
protocol from the Third International Stroke Trial (IST-3), a double
blind placebo controlled trial of rt-PA for acute stroke.  I can
confirm that in this trial the uncertainty principle only applies as an
exclusion criteria prior to randomisation.  Any individual
randomised into the trial will be followed-up.  If for any reason they
did not receive the trial treatment they would still be followed up
and the circumstances would be fully documented.  All analyses
are by intention-to-treat.
As before please contact me if you require any further information.
Regards
Anne Leigh Brown



Date sent:              Fri, 17 Aug 2001 15:59:19 -0400

Send reply to:          [log in to unmask]
From:                   Jeanne Lenzer <[log in to unmask]>
Subject:                FW: uncertainty principle
To:                     [log in to unmask]

> -----Original Message-----
> From: Jeanne Lenzer [mailto:[log in to unmask]]
> Sent: Friday, August 17, 2001 3:44 PM
> To: [log in to unmask]
> Subject: RE: uncertainty principle
>
> Hi Victor -
>
> Thank you very much for your explanation.  It seems to me (and forgive
> me, I'm merely a journalist here trying to learn) - but it seems to me
> that what you say is true - but that it may not be relevant to the
> study protocol that included that paragraph.
>
> The uncertainty principle, it seems to me, is what should be operative
> in order to determine whether a study should be undertaken at all.  Do
> we know if drug A is definitely better than placebo?  If we don't know
> the answer to that, then and only then, is a study ethical.  However,
> once we determine that we are uncertain and a study is ethical - to
> allow clinicians to remove patients from randomization still seems to
> be risky to me and I wonder about that undermining the study's genuine
> randomness.
>
> For example, what if a clinician has a bias that the drug must work
> better than placebo and therefore chooses to pull out a number of the
> "sicker" patients but not the less sick patients because he or she
> thinks "it's really important that my patient get the active drug"?
> Could that change the spectrum of patients receiving treatment vs.
> non-treatment?  Also, what if the researcher has vested interests (is
> receiving drug company funding) - could she or he then (consciously or
> unconsciously) pull patients out of the randomization process in a
> manner that influences the process?  I guess a lot of this depends on
> when the patient is pulled - before or after randomization?  But even
> then, prior exclusion of all "really sick" patients could affect the
> process?  Or am I hopelessly lost?
>
> Thanks much
> jeanne
>
> -----Original Message-----
> From: [log in to unmask] [mailto:[log in to unmask]]
> Sent: Friday, August 17, 2001 2:55 PM
> To: [log in to unmask]
> Subject: RE: uncertainty principle
>
>
> This is not liberal, it is ethical.  If there is no doubt that active
> treatment is in the best interest of the patient then not offering it
> to her would be substandard care (same for clearly contraindicated
> medication). Only those patient-physician duets that are certain that
> they do not know whether treatment A is better than treatment B are in
> a reasonable situation to join the study. There is no way around this.
>  The dangers of not following this principle is patient desertion,
> off-study use of study medication, and other forms of noise that will
> limit the ability of the study to show a treatment effect resulting in
> a monumental waste of time and resources for all involved. Does this
> answer your question? V
>
> > ----------
> > From:         Jeanne Lenzer[SMTP:[log in to unmask]]
> > Reply To:     [log in to unmask]
> > Sent:         Friday, August 17, 2001 1:32 PM
> > To:   [log in to unmask]
> > Subject:      uncertainty principle
> >
> > Could anyone explain the pros and cons of the following:
> >
> > Uncertainty principle (absence of proof): Further inclusion and
> > exclusion criteria are not specified precisely but are guided by the
> > uncertainty principle (or absence of proof for that particular
> > patient). If, for whatever reason, the clinician is convinced that a
> > patient fulfilling the above criteria should be treated, that
> > patient should be given open label drug and not randomized. If the
> > clinician is convinced that a patient should not be treated (for
> > whatever reason), the patient should not be included in the trial.
> > Only those patients who fulfill the eligibility criteria AND for
> > whom the clinician is still substantially uncertain about the
> > balance of risks and benefits of active drug should be randomized.
> >
> > Can this kind of enrollment liberalism cause a failure of true
> > randomization?  Does it introduce spectrum and other biases?
> >
> > Thank you any and all for any insight you can give this underfed
> > journalist.
> >
> > Jeanne Lenzer
> > Freelance writer
> > 191 Otens Rd.
> > Ellenville, NY  12428
> > USA
> > Office phone: 845-647-3670
> > Office fax: 845-647-3670
> > Cell phone pager: 914-399-5001
> > [log in to unmask]
> >
> >
> >



________________________________________

Anne Leigh Brown
Neurosciences Trials Unit
University of Edinburgh
Bramwell Dot Building
Western General Hospital
Crewe Road
Edinburgh EH4 2XU
UK
e-mail:    [log in to unmask]
Telephone: 0131-537-2930
Fax:       0131-332-5150
________________________________________