Will Rogers
Big Pharma
has a number of ways, many of which have been described in this blog, of making
their drugs look a lot better than they actually are. And some
psychotherapy researchers use the techniques to push their favored school of thought. I
recently came across another one of which I wasn’t aware.
It is easiest to see
with drugs used for cancer chemotherapy, but can be applied in other cases.
It is called the Will Rogers
phenomenon (and is also called Stage
Migration). It is an apparent epidemiological paradox. The Rogers reference
comes from a remark made by the famed humorist Will Rogers about migration
during the American economic depression of the 1930's: "When the Okies
left Oklahoma and moved to California, they raised the average intelligence
level in both states."
With cancer drugs, it comes from changes over time in the way the
severity of the disease is assigned to patients - how the various stages of a disease are determined in each case. (Stage I is when the cancer is smallest, has
not spread, and is usually the most easily treated. Stage IV is the most
advanced with metastases). The issue comes about because the technology for
staging a cancer in a given patient has improved significantly. This can
produce spurious improvements in stage-specific prognosis, even though the
outcome of individual patients has not changed.
New imaging tools have allowed detection of cancer metastases
before they became evident clinically. As a result, more patients are
classified into the more severe metastatic disease stage from the less severe
single tumor stage. Such a 'stage migration' resulted in an improved survival
of patients in both the less and the more severe disease stages. (Multiple
sclerosis is another disease where this sort of thing has taken place).
Some studies compare a new treatment to the treatment of so-called
historical controls who had received other treatments. This is usually done
because carrying out placebo-controlled studies in potentially dying patients
is unethical. The Will Rogers phenomenon is recognized as one of the most
important biases limiting the use of historical controls groups in experimental
treatment trials.
Essentially, the use of different diagnostic criteria may
generate spurious improvements in the medium-term prognosis which then may be
wrongly interpreted as treatment effects.
In psychiatry and psychology, placebo controlled studies can be
done ethically, but a variation of the Will Rogers phenomenon can still take
place because of how rigorously DSM diagnostic processes are applied to patients. When I
first started training, the criteria for major depression and mania were
rigorously applied in treatment studies; now they are often applied sloppily –
on purpose.
Chronic unhappiness, which may respond very well to cognitive
behavioral psychotherapy, is often now misdiagnosed as the more serious major
depressive disorder. If you have a bunch of those folks in your psychotherapy
outcome study, CBT can be “shown” to be effective in major depression by
including people in your study who really don’t have major depression.
The more serious depressions respond better to antidepressant medications.
Since most antidepressants are now generic, drug companies who want doctors to use
other, more profitable drugs like Latuda can do the same thing to “show” that antidepressants
are actually less effective than they
actually are. Placebo response rates in antidepressant studies have gone up
about 10% every decade, and this is what I believe to be the reason.
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