Robert F. Kennedy Jr. talks with reporters in the lobby of Trump Tower in New York, Tuesday, Jan. 10, 2017, after meeting with President-elect Donald Trump. (AP Photo/Evan Vucci)[/caption]

Robert F. Kennedy Jr. considers himself an environmentalist. While advocating for the environment, he has become particularly concerned about the effects of mercury on human health. This in itself is reasonable, and there is broad scientific agreement that we should make efforts to minimize human exposure to mercury.

But Kennedy goes beyond reasonable recommendations based upon scientific consensus. He has become part of what we call, “The Mercury Militia” who have become unmoored from reality in their zeal to combat the perceived evils of mercury. The mercury militia further became tied to the anti-vaccine movement when it was claimed that the mercury in some vaccines was causing harm (it doesn’t). He has become a visible example of how someone can cocoon themselves in their own reality.

In a recent interview for Stat News Kennedy tells a number of falsehoods about vaccines. In essence he is lying, although it is possible he believes the lies he tells. Kennedy has apparently dedicated a large portion of his life to this issue, publicly advocates for his position, and certainly has resources at his disposal. And yet he gets basic facts about vaccines hopelessly wrong. How does that happen?

Paul Offit has written an excellent take down of Kennedy’s interview, explaining many of his falsehoods. For example, in the interview Kennedy claims:

We need to do double-blind placebo testing. Because particularly when it comes to injecting aluminum or mercury into babies, the consequences may be latent. In other words, they may not manifest or diagnosed to age 3 or 4. So the current protocols, which require testing for vaccines of sometimes as little as 48 hours, are not going to disclose the kind of dangers that the public and the regulators ought to know about. The hepatitis B vaccines that are currently approved had fewer than five days of safety testing.

As Paul points out, this is demonstrably wrong, but let me go into a bit more detail. It is not difficult to find relevant studies, using either PubMed, or by going to the CDC which conveniently links to a few of the important studies. There is one short term study looking at infants, who are typically vaccinated for Hep B at birth.

During this time 3302 infants were vaccinated within 21 days of birth with hepatitis B vaccine, and 2353 were not. There were no significant differences between vaccinated and unvaccinated newborns in the proportion of infants who received care for fever (0.8% vaccinated and 1.1% unvaccinated, P = 0.28), allergic reactions, seizures or other neurologic events in the first 21 days of life. Vaccinated newborns were significantly less likely to undergo microbiologic evaluation for possible sepsis.

I have no idea where Kennedy got “five days” from. In this study, which is considered a short term study looking for immediate reactions, they tracked the infants for 21 days. Perhaps if there was an infant in the study vaccinated on day 16 they would have only been followed for 5 days post vaccine, but most infants are vaccinated at birth.

What is going on here is a massive exercise in cherry picking. This is a core strategy of propaganda and marketing by distorting reality (i.e., lying). The FDA requires a series of safety testing for new vaccines and drugs. These include preclinical, and then a progression of clinical trials. You can, of course, focus on some of the preliminary studies and claim that they were inadequate, and fail to mention the later larger studies. I could say, for example, that some studies used for drug approval involved only 20 or so subjects and don’t even test whether or not the drug works. This is completely true, but also very misleading. While such phase I trials are used in the process of approval, they are not sufficient for approval.

Kennedy also ignores the fact that vaccines in particular are closely monitored after they are approved. Even in a study with thousands of subjects, we may miss adverse effective once given to millions of subjects and followed for years. So here is a study involving 350,000 infants, showing no risk from the Hep B vaccine. Databases have been used to follow the effects of Hep B and other vaccines for years.

It seems clear that Kennedy is not trying to look at all the evidence to answer the question – are vaccines safe. He is looking through the evidence to find support for his position that they are not safe. The evidence he finds, no matter how cherry-picked or out of context, then becomes confirmation for his position. He remembers those pieces of information, which may become distorted further over time to support his narrative, until he eventually comes to believe a list of “facts” that are demonstrably false. This is motivated reasoning and confirmation bias.

Here is a typical exchange from the interview:

If something happened four or five years out from an event, how do you know which event to attribute it to? Well, the answer to that question, of course, is double-blind placebo testing. You have a control group and you have a study group. Sir, that’s done all the time. That is done all the time. It’s not required for vaccines. Vaccines are tested that way all the time. You’re wrong about that. It is not required for vaccines. So most of the vaccines — and I know this is surprising to you, and it’s shocking to most people, because journalists like yourself assume that vaccines are encountering the same kind of rigorous safety testing as other drugs, including multiyear double-blind placebo testing. But the fact is that vaccines don’t. And the reason for that is they’re classified as biologics. I’ve read a lot of vaccine studies. And they are double-blind placebo tested. No, you’re wrong about that. … But in any case, none of them have more than a few months of double-blind placebo testing, which will not allow you to spot illnesses like autism that aren’t diagnosed before five years. Second of all, in most vaccines, for example the Gardasil vaccine, they don’t use true placebos.

The interviewer (in bold) of course is correct. But you can see the process Kennedy is using here to again distort reality. There are many placebo-controlled trials of vaccines for safety and efficacy. The overall risk vs benefit ratio must be favorable. This is required by the FDA. (We are also not the only country to test vaccines.) What Kennedy is doing is a classic denialist strategy – demanding the one true perfect bit of evidence.

Especially in medicine, no one study has it all. Studies are more powerful when they are highly controlled, involve a lot of subjects, gather a lot of detailed data, and follow those subjects for a long time. It is difficult and expensive to do all of those things at the same time, however. So researchers will tend to cobble together this information from various studies. You can do detailed analysis of a small number of subjects, or a large number for a short time, or gather retrospective data on a large number for a long time, etc. But if your looking for one perfect definitive study, you are probably not going to find it.

What this means is that you can point to some weakness in any study to dismiss its results, even if other studies shore up that weakness. So this study was too short, and that study was open label, and this other study was retrospective. They all show that vaccines are safe, and taken together are powerful evidence for safety. But in Kennedy’s mind, he attributes the cherry picked flaws (really trade-offs) in individual studies to “vaccine studies.”

There is likely some defensiveness at work as well. Kennedy gets challenged on some of his assertions, and he finds evidence to support his position – rather than modifying his position to match reality.

This is all nothing new. As psychologists have documented in many studies, this is standard behavior for humans. Once we have a narrative we care about, we are really good and arranging information to seem to support that narrative. Kennedy has been doing this for years, and he has erected an elaborate construct of deception, mostly to deceive himself. He liberally uses conspiracy theories and misinterpretation of scientific information to create his narrative construct.

The end result is that he tells outright lies about the evidence, and feels confident enough to say them in a public interview as if they are facts.

But as Paul Offit points out, these are dangerous lies and the public record needs to be corrected.