The
moral imperative to know the harms of procedures is great.
by Theodore Dalrymple in PJ Media
Like politicians, doctors are
inclined to believe that doing something (especially when it is them doing it)
is better than doing nothing. They mistake benevolent intentions for good
results, believing that the first guarantee the second. How can philanthropy go
wrong?
Besides, doing something stimulates
the economy in a way that doing nothing cannot possibly match. If people did
only what was necessary, or what was good for them, or what was right, the
whole of our economy would soon collapse.
Be that as it may, and for whatever
reason, clinical trials that have positive results are more likely to be
published than those with negative results. Thanks to several well-publicized
scandals, this publication bias, as it is called, is on the decline.
GlaxoSmithKline, one of the largest pharmaceutical companies in the world, has
promised that henceforth it will publish the results even of trials that are
unfavorable to their products as well as those that are favorable.
A paper by Danish researchers just
published in the British Medical Journal assesses the extent to which
published reports of trials of screening procedures, such as mammography,
colonoscopy, PSA-levels, etc., report their harmful effects and consequences as
well as their positive ones.
This is particularly important
ethically because screening reverses the usual relationship between patient and
health-care system. In screening it is the health-care system that initiates
the contact, not the other way round. Screening is offered to healthy people,
or at least to those complaining of nothing; moreover, the chances of benefit
from screening are often slight and those who do benefit from them do so in a
sense at the expense of those who are harmed by them. The moral imperative to
know the harms of screening is therefore great.
It will probably by now not come as
a surprise to readers to learn that the Danish researchers found reports of
experiments on screening procedures to be peculiarly lacking in details about
the harmful effects of those procedures. They considered reports on 57 trials
for screening for several different kinds of cancer (that is, all those that
had been done in the world to an acceptable standard), using ten different
technological techniques.
These trials involved 3,416,036
participants. They looked to see whether the reports contained quantified
evidence about seven possible harms of screening: overdiagnosis, false positive
findings, bodily complications from screening procedures, negative psychosocial
consequences of screening, additional numbers of invasive procedures consequent
upon screening, all-cause mortality (important because extra surgical
procedures, for example, would have a mortality rate), and the withdrawal of
participants because of complications of the screening procedures. It is
necessary to know these things before a doctor can properly advise a patient to
have a screening procedure, or before a patient can make an informed decision.
In only one of the 57 trials was a
figure given for the number of withdrawals from completion of the trial because
of complications caused by the screening procedure. In only two trials were the
figures given for false positives and four trials for overdiagnosis. This
contrasts with 51 trials that measured cancer-specific mortality, the reduction
of which is the aim of screening procedures. All-cause mortality — more
important to the patient than cancer-specific mortality — was measured half as
often cancer-specific mortality.
The authors are uncompromising in
their conclusion: doctors are recommending procedures on a vast scale on the
basis of inadequate knowledge that also precludes informed consent on the part
of patients. This is because the harms as well as the benefits of a procedure
should be known before recommending or agreeing to it. All the more is this so
where the initiative for the procedure comes from the doctor and not from the
patient.
******
Theodore Dalrymple, a physician, is
a contributing editor of City Journal and the Dietrich Weismann Fellow at the Manhattan Institute.
His new book is Second Opinion: A Doctor's Notes from the Inner
City.
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