Regular readers of the Mental Elf may remember my previous blog which looked at a series of papers examining the placebo effect in relation to depression and the use of antidepressant medication. You can find it here along with a placebo primer by Ben Goldacre here.
To recap, the placebo effect refers to the effect of a simulated or otherwise ineffectual treatment. It has been known about for more than 200 years. Placebos are often used as control treatments in trials of medicine, the rationale being that the medicine should outperform the placebo (commonly a sugar pill) in order for it to be regarded as efficacious.
In the paper I’ve been asked to review for the Mental Elf (Rutherford et al, 2014) the authors chose to examine the placebo response in antipsychotic clinical trials. Rutherford and colleagues note at the beginning of the paper that placebo response rates in trials of antipsychotic medications are increasing. That is, difficulties seem to have been improving to a greater extent more recently than in the past despite the placebo itself remaining the same. The authors sought to determine the causes of this increase in placebo response rate. They argued that this phenomenon increases the cost of drug development, delays the availability of new antipsychotic medications and means that pharmaceutical companies spend less money on psychiatric research.