Doctors’ beliefs influence patients’ pain, study finds.

Researchers have found the placebo effect, where a medical treatment with no active ingredient still works, is “contagious” and can be passed on from doctors to patients.

The finding, reported in the journal Nature Human Behaviour, suggests doctors with a stronger belief in their treatments may enact a self-fulfilling prophecy, unwittingly delivering more effective medicine.

The placebo effect is well established. Simply believing an injection will take pain away can make it work, even when the syringe is just full of saltwater.

Those expectations drive powerful changes in the brain, releasing the body’s own internal pain killers or “endogenous opioids”, which then faithfully deliver up the result.

But the researchers, led by Luke Chang from Dartmouth College in New Hampshire, US, were intrigued by evidence that the beliefs of the “treater” can also influence whether something works.

For example, when school teachers are led to believe certain students are “growth spurters”, those kids do better on a standardised test at the end of the year.

What would happen, the authors wondered, if you could get doctors to think a medicine was stronger than it actually was. Would their patients do better on it?

Read the full story in Cosmos magazine here