Thursday, October 11, 2018

Another Pharma Trick for Overstating the Effectiveness of their Drugs: The Will Rogers Phenomenon

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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