EXAMPLE 6 Sham surgery
“Randomized, double-blind, placebo-controlled trials are the gold standard for evaluating new interventions and are routinely used to assess new medical therapies.” So says an article in the New England Journal of Medicine that discusses the treatment of Parkinson’s disease. The article isn’t about the new treatment, which offers hope of reducing the tremors and lack of control brought on by the disease, but about the ethics of studying the treatment.
The law requires well-designed experiments to show that new drugs work and are safe. Not so with surgery—only about 7% of studies of surgery use randomized comparisons. Surgeons think their operations succeed, but innovators always think their innovations work. Even if the patients are helped, the placebo effect may deserve most of the credit. So we don’t really know whether many common surgeries are worth the risk they carry. To find out, do a proper experiment. That includes a “sham surgery” to serve as a placebo. In the case of Parkinson’s disease, the promising treatment involves surgery to implant new cells. The placebo subjects get the same surgery, but the cells are not implanted.
Placebos work. Patients on placebos often show improvement and their inclusion produces a better experiment. As more doctors recognize this fact, more begin to ask, “If we accept a placebo in drug trials, why don’t we accept it in surgery trials?” This is a very controversial question. Here are two arguments about whether placebos should be used in surgery trials.
Yes: Most surgeries have not been tested in comparative experiments, and some are no doubt just placebos. Unlike placebo pills, these surgeries carry risks. Comparing real surgeries to placebo surgeries can eliminate thousands of unnecessary operations and save many lives. The placebo surgery can be made quite safe. For example, placebo patients can be given a safe drug that removes their memory of the operation rather than a more risky anesthetic required for the more serious real surgery. Subjects are told that they are in a placebo-controlled trial, and they agree to take part. Placebo-controlled trials of surgery are ethical (except for life-threatening conditions) if the risk to the placebo group is small and there is informed consent.
No: Placebo surgery, unlike placebo drugs, always carries some risk, such as postoperative infection. Remember that “the interests of the subject must always prevail.” Even great future benefits can’t justify risks to subjects today unless those subjects receive some benefit. We might give a patient a placebo drug as a medical therapy because placebos work and are not risky. No doctor would do a sham surgery as ordinary therapy because there is some risk. If we would not use it in medical practice, it isn’t ethical to use it in a clinical trial.