Surgical placebo

Ian Harris argues that perhaps more than half of the frequently performed surgeries are placebo , and that blind tests with control groups are necessary.



Ian Harris, professor of orthopedic surgery at the University of New South Wales in Sydney, Australia, has written a book called Surgery, The Ultimate Placebo. I have not read the book, but I saw on YouTube his excellent lecture on the same topic.... In it, he evaluates the many commonly performed surgeries and opens his eyes to the fact that they are often no more effective (if not worse) than placebos or drugs that have not been tested. He covers the history of sham surgery research, talks about the placebo effect, and explains why many surgeons ignore various evidence and continue to perform ineffective surgeries. Also from this lecture you can learn the methods of critical thinking.





Harris first became aware of skepticism at 18 when he watched a television documentary in which James Randi and Dick Smith conducted controlled tests on control groups of dowsers. The researchers buried 10 pipes and asked dowsers to determine which one was running water. When they were told which of the pipes was active, they all identified it correctly, but when he did not know this, only 12% of the answers were correct. Harris was impressed that such a simple test could easily refute a basic statement.



When he recently reviewed this film, he was impressed with the reaction of the dowsers when they were shown that dowsing didn't work. In them he recognized surgeons, whose operations were not checked and did not help patients. They came up with various excuses and hypotheses about why the experiments did not give the expected results and said that they would not abandon certain operations "because they work."



In the early 20th century, a common operation for heart disease was ligation of the internal mammary artery. Then it seemed obvious that it worked: the patients were getting better. In 1939, an experiment in sham surgery showed that if a surgeon just made an incision, but did not dress it, then exactly the same number of patients got better.... The surgeons listened and stopped dressing.



Harris takes us on a historic tour of research-proven surgeries. Surgeons often reject evidence and come up with explanations for why certain operations did not work in these studies - they remain convinced that these operations work, and everything is in their hands. When they refuse to stop performing these operations, their excuses sound the same as those of dowsers. They insist on continuing to do these operations "because they work" (in their experience). Billions of dollars are wasted on hundreds of thousands of operations, although these operations have been proven ineffective (or tests were not even performed, which means these operations were not even compared to inaction).

False analogies and misleading reasoning

Often the theory claims that the operation should work, although biological validity does not mean anything - only tests can show that it really works. Dr. Harris says that "you can bring a biological mechanism for anything."



The parachute analogy tells us that we don't need to conduct a randomized controlled trial to test the performance of parachutes. Dr. Harris says he has often seen the technique applied to procedures that were ultimately useless.



Comparative efficacy studies are done to compare two different methods of something (like steroid injections for back pain), but they don't tell us if either method works. They might be better described as studies of comparative inefficiency. The first step was to introduce a control group and compare steroid injections versus no injections.

Perception of efficiency

Perceived efficacy is a combination of two factors: the specific effects of the treatment and its placebo effects.



There are shortcuts in thinking that all people are programmed for. They assume that correlation means causality and fall into the post hoc ergo propter hoc fallacy (If event X happened after event Y, then event Y caused event X). Such abbreviations in reasoning processes often lead to errors. Improvement may be related to something other than surgery, such as natural history of the disease, regression to the mean, or concomitant treatment.



Improvement can be seen by the patient (sometimes false perceptions due to placebo factors or misinterpretation) and / or by the clinician due to measurement errors, accumulation of errors in reports, confirmation bias and many other aspects. Doctors rate the effectiveness of their treatment higher than their patients. The doctors' perception is wrong; they constantly overestimate the benefits and underestimate the harm of their treatment.

Treatment is not always necessary

Harris tells the story of Archie Cochrane, after whom the Cochrane Collaboration on Systematic Analysis was named. As the only doctor in a POW camp during World War II, he was responsible for 10,000 prisoners, many of whom suffered from open wounds, dysentery, typhoid fever and other serious illnesses. His requests for doctors and medicines were rejected by his German invaders, who said that doctors were not needed here. In six months, only 4 prisoners died, each of whom was shot for attempting to escape. All others recovered without treatment.



Harris's story distorts the truth, but it serves as a vivid illustration of an important fact: recovery often occurs without any treatment. Cochrane's experience made him question what is being done in the name of medicine. The patients were kept in bed for a week after the heart attack, not because of any evidence, but simply "because it makes sense." Cochrane conducted controlled research and found that bed rest actually harmed people.

Surgery often works like a placebo

Harris describes many factors that influence a patient's response to placebo. A systematic review found that placebo was as effective as surgery in over half of the cases studied. All recent trials comparing surgery to placebo have shown that surgery is no better than placebo.



He refutes all of the surgeons' arguments in favor of continuing operations that have been tested and proven to be ineffective. The real reason is that they still believed these procedures to be effective, just as dowsers continued to believe that they could find water with a fork. Tradition and personal experience trump science and reason.



Science is simply a systematic way to reduce errors. It's imperfect, but better than any other approach. Blind testing is the least biased way to measure performance.

Ethical issues

Some people argue that it is unethical to do bogus transactions. Placebos are unethical in clinical practice to treat an individual, but not in research where they are needed to find the truth and balance harm and benefit for large groups of people and to prevent future harm. Of course, doing ineffective transactions is unethical. When it comes to medicine-based science, we constantly question the ethics of selling nutritional supplements with slogans and statements that have never been properly verified. Some herbs may be harmless, but surgery always carries the risk of infection, tissue damage, and side effects. It's also expensive: millions of dollars are spent worldwide on procedures that put patients at risk without any benefit.

Conclusion: Evidence Needed

Harris concludes by saying that we should treat new surgical procedures as new drugs and pay only for those proven to be effective. Most of the surgical procedures performed today have not been blindly tested.



Patient advice: It is possible to get a second opinion and you should always ask your surgeon if there is evidence showing the benefits and risks of the procedure and what you can expect if the surgery is not done.

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