The power of faith has its place in medicine. That’s one of the implications of a new study published recently in the journal Nature Human Behavior. It investigated how a clinician perceives the treatment they provide can affect its efficacy from the patient’s perspective. Essentially, the study found that the benefits of a placebo can transfer from provider to patient.

For the study, the researchers simulated a medical treatment scenario with grad students, who acted as either patients or clinicians. The “patients” then received a controlled heat stimulus and one of two types of cream. Researchers told the “provider” group that only one of the creams was an actual medication, but they were the same petroleum jelly placebo. When the clinician thought the medication was real, the “patients” reported significantly lower pain levels.

The main reason patients could internalize what their provider believed was through facial expressions, according to the Nature Human Behavior article. Researchers filmed the interactions with a GoPro camera and used a computer to look for nose-wrinkling, lip-curling, and brow-lowering.

They found that the “clinicians” showed less pain in their faces when they believed the “patients” had received an effective cream (versus the placebo). As a result, their “patients” showed less pain on their faces and through other measures. These patients also reported that their providers were more empathetic than those in the other group.

As the study’s lead author Luke Chang, Ph.D., a psychology professor at Dartmouth College, explained: “After the clinical interaction with doctors, patients not only showed the same beliefs about treatment effectiveness but also subjectively perceived less pain as a result of the treatment despite there being no real difference between treatment and control conditions.”

Another interesting aspect of the study is its implications for the “interpersonal-expectancy effect,” a phenomenon that occurs when one person holds a belief, acts per that belief toward another person, and, as a result, the second individual behaves in a way that confirms the original belief.

The research applying the interpersonal expectancy effect to clinical settings is lacking, Dr. Chang notes, but “a few studies have provided positive evidence that healthcare providers’ or caregivers’ expectations could potentially affect patients’ treatment outcomes.”

So, what’s the takeaway for clinicians? Be aware of what your nonverbal gestures tell your patients; a little empathy goes a long way.