The U.S. Centers for Disease Control and Prevention (CDC) reportedly has plans to perform a large study on a “possible connection” between vaccines and autism—a topic of interest to Robert F. Kennedy Jr., Secretary of Health and Human Services, despite plenty of research showing no such connection exists.

During his Senate confirmation hearings, Kennedy was asked by Republican senator and physician Bill Cassidy about his views on vaccines and autism. “Will you reassure mothers unequivocally and without qualification that the measles and the hepatitis B vaccines do not cause autism?” Cassidy asked.

“If the data is there, I will absolutely do that,” Kennedy replied.

Of course, the data is there—in abundance. There is ample scientific evidence that vaccines do not cause autism. Yet Kennedy and those who discount this research claim that it is either flawed or insufficient to disprove a possible link. That raises the question: could more “data” change their minds?

If a lack of “good data” is truly driving people to avoid vaccines, it would be important to know, exactly, what new data could possibly change minds. Considering that most parents are probably not reading and appraising scientific studies themselves (either because they’re busy or because scientific studies are not really written for general audiences), this question is best asked to the high-profile vaccine skeptics in which some parents have placed their trust and whose opinions are taken seriously by millions of Americans.