How Should Doctors Frame the Risk of a Vaccine's Adverse Side Effects? It Depends on How Trustworthy They Are.

How health workers frame their communication about a vaccine's probability of adverse side effects plays an important role in people's intentions to be vaccinated.In 4 experiments, we manipulated the trustworthiness of a physician and how the physician framed the risk of adverse side effects of a COVID vaccine.Positive framing given by a trustworthy physician promoted vaccination intention but had null effect or did backfire when given by an untrustworthy physician.The effect occurred over and above participants' attitude toward the health care system, risk perceptions, and beliefs in COVID misinformation.