New controversies abound in America, but one that has persisted over time, even after being scientifically debunked over and over again, is the vaccine controversy. Unfortunately for herd immunity and individual health and wellness, the vaccine controversy extends well past childhood vaccines and into vaccines that are recommended for adults, such as the influenza (flu) vaccine. This post shows how behavioral economic concepts and decision theory play a role in what’s often referred to as “vaccine-hesitancy,” but I first want to draw your attention to the health and economic costs the nation incurs when people don’t get vaccinated against the flu.
“Herd immunity” protects infants and people who are too sick to be vaccinated from preventable disease. It occurs when a significant proportion of the population is immune to a contagious condition because they have been vaccinated against it. When this occurs, infants and people whose immune systems are compromised have a much smaller risk of coming into contact with the illness in question because much of the community is already protected. Influenza vaccination is important enough to individual and public health that multiple HEDIS measures track the percentage of health plan members who are vaccinated.
Reduced flu vaccination rates, also known as reduced vaccination coverage, can even present a problem for those who have been vaccinated against the flu. Due to the challenges of predicting which strains of flu will affect the nation in a particular flu season, flu vaccines vary in their effectiveness from year-to-year.[i] The Centers for Disease Control and Prevention (CDC) estimates the overall effectiveness of the influenza vaccine in the U.S. to in the U.S. varied between 10% and 60%…” between 2004 and last year’s flu season. That means that in any given year, even if you get vaccinated, you may still contract the flu.
During the 2015-2016 flu season, nearly 42% of U.S. adults were vaccinated. That’s a drop of 2% from the previous season and it means that 58% of the U.S. adult population was unvaccinated. That could include your neighbors and coworkers, who could come down with the flu and pass it along to you. That’s a form of sharing that none of us is really interested in engaging in. “But it’s just the flu,” you say. “No big deal.” Ah, that is where you are incorrect, my dear reader. The flu kills. The CDC estimates that up to 56,000 people have died each year in the U.S. since 2010. And you know how you keep hearing about high hospital bills that are bankrupting Americans? Well, the flu sends up to 710,000 to the hospital each year. That means some big medical bills and lost income for something that could have been prevented with a flu shot. And the cost to the national economy? Nearly $6 billion in 2015, topping the economic cost of all other vaccine-preventable illnesses examined in one study. The researchers found that most of the economic burden caused by vaccine-preventable illness is caused by people who chose not to get vaccinated (about 79% of the total burden). When people make a decision not to get vaccinated, they’re making a decision that affects us all, and in multiple ways. So if the influenza vaccine can prevent all of this physical and financial suffering, what gives?
The Vaccine Controversy
The term “vaccine-hesitancy” is relatively new. Think of it as the middle section of a continuum that ranges from people who demand vaccines to those who totally refuse all vaccines. But a simpler definition that better aligns with the public’s understanding of the term is “an active desire to defer or omit any of the vaccines routinely recommended…” In the U.S., controversy over vaccines dates back to the 1850s, and today is driven by a number of factors, from the sources Americans often consult for health information, to increasing societal mistrust in the nation’s institutions (e.g., business, media, and governmental institutions). Let’s face it – the internet is a platform for misinformation. One study, published in 2013, found that vaccine-hesitant people are more likely to use the internet as an information source than those who either get vaccinated or report that they are undecided about flu vaccination. Another driver of vaccine-hesitancy is the historical exploitation of minority communities in medical research which generated mistrust of the healthcare system that has been handed down through generations. This mistrust leads some to question medical guidelines and avoid engaging with the system.
But the Big Fish in this story is a discredited British researcher who published a study that claimed there was a link between the childhood MMR vaccine and autism (the paper has since been retracted). The author of that 1998 study, Dr. Andrew Wakefield, subsequently had his medical license revoked and a prominent medical journal reported that Wakefield’s research was fraudulent. The study’s co-authors no longer want anything to do with the work after learning that Wakefield was being paid by a law firm that was preparing to sue vaccine companies when he published his study. Dr. Wakefield had omitted this important detail from the report. In fact, the British Medical Journal (BMJ) reported that the researcher received the equivalent of more than a half-million dollars from the firm. But before the BMJ investigation broke the case open, the damage was done. Vaccination rates fell in the U.K and U.S. The discredited Wakefield study, which BMJ calls “an elaborate fraud,” tarnished the image of life-saving vaccines.
Another issue implicated in the vaccine controversy is the inconvenient fact that new scientific findings are released all the time and they sometimes conflict with each other. This cannot be helped – it’s the nature of science. But the public can find it confusing and confusion can lead to inaction. In 2012, researchers reported a paradox – people who are regularly vaccinated against the flu were less protected than those who don’t. That is exactly the type of scientific finding that leads to internal conflict and anticipated regret for people who are making decisions about whether to get vaccinated. As another example, some people fear that flu vaccines actually cause flu (they do not).[ii] So what’s the average American supposed to think when combined with the fact that vaccination does not translate into 100% protection?
Cognitive Biases at Play
Well, I’m not here to tell you what to think, but I can tell you about some of the cognitive biases that affect the way people make decisions about vaccinations. Cognitive biases are tricksters that can cause people to make poor decisions. They’re studied in multiple disciplines that have a common theme – the study of how people process information and behave. They’re very useful for explaining why people make irrational decisions and fail to select the options we hope they will select.
There are many types of heuristics and cognitive biases I could tell you about here, but I’m going to focus on three that are particularly relevant to the decision not to get vaccinated against the flu. The first is confirmation bias. Confirmation bias likely impacts most of our daily lives whether we like it or not. It occurs, in part, when you notice or seek out information that confirms your own beliefs, while dismissing information that contradicts your beliefs. For example, if you have strong feelings about climate change or another hot button topic, information that confirms your beliefs is going to stand out when you see it, while you may choose to disregard stories that present alternative viewpoints, believing that they have little credence. Perhaps, if you have strong political views, you seek out information on websites that align with your political views and actively avoid websites that are on the other side of the political spectrum. Or, in the case of vaccines, if you are vaccine-hesitant, information that asserts that there is an association between vaccination and autism may stand out to you more readily than information about vaccines saving lives. We all entertain our own confirmation bias from time-to-time. It takes active monitoring of your own thought processes to avoid doing it and it’s hard to keep up with that monitoring 24 hours a day! Researchers from Yale and UCLA have posited that this type of bias, along with other defensive biases, are adaptive and serve to help you maintain a sense of individual self-worth.[iii]
The bandwagon effect is especially relevant now that social media is so pervasive in our society. You’ve heard of things “going viral,” of course. The bandwagon effect on vaccine hesitancy occurs when society begins to adopt the views of those who are vaccine-hesitant, increasing the probability that additional people will adopt vaccine-hesitant viewpoints. The bandwagon effect provides some explanation for social trends, like the use of Twitter and Facebook. Human beings are influenced by others around them. When they hear about people refusing vaccines, some will jump to a conclusion that that must mean there is something bad about vaccines. Fortunately, there are ways of addressing this form of bias. Member outreach that uses social norming techniques and works to improve member self-efficacy can counteract the bandwagon effect.
Finally, the availability heuristic is a mental shortcut. When you weigh the pros and cons before making a decision, if you find yourself placing more emphasis on the cons because past examples are more memorable than examples of the pros, you’re using the availability heuristic. It’s easier to remember the bad than it is to remember the good! A lot of times, the good just seems like the status quo, so it doesn’t stand out in your memory. For example, you may remember a time when you went and got your flu shot, but you contracted the flu anyway and lived in misery for a week. On the other hand, the years when you received a flu shot and remained healthy all season probably go unnoticed and fade from memory.
Heuristics help people make decisions under uncertain conditions, but they can lead to errors in logic that result in poor decision-making. We at Eliza have the expertise and experience required to successfully tackle heuristics and biases head-on! Using a principle from decision science and behavioral economics, called “loss aversion,” Eliza crafts messages that use loss aversion to health plans’ advantage. For example, we can let members know that skipping the flu shot can dramatically increase the chance of getting the flu (by 400%)![iv]
Theory Ties It Together
The use of the loss aversion concept dovetails nicely with our use of the Health Belief Model (HBM), a well-regarded theory frequently used in behavior change communication. The HBM is made up of five key factors that can be used to understand and predict health behaviors. The first of these is “perceived susceptibility,” or the degree to which a member believes that he or she is likely to come down with the flu. Perceived severity, another key piece of the HBM, ties-in here, as well. Using a conversational tone and simple-to-understand language, rather than providing a litany of statistics that aren’t very meaningful or impactful for the average person, we can also remind members that the flu is very unpleasant by invoking memories of members’ previous flu experiences. The final three pieces of the model are perceived benefits, perceived barriers, and cues-to-action. Previous studies have found that the perceived benefits portion of the HBM is the most important predictor of influenza vaccination (e.g., belief that getting vaccinated protects the member’s family and that the flu shot is safe). Eliza’s messaging serves as a cue-to-action and we explain the benefits of vaccination. We can also assess member barriers so that plans can evaluate whether additional intervention is warranted.
The HBM is just one of several health communication theories Eliza employs, in combination with decision theory and behavioral economic concepts, to drive member behavior change. Our designers have advanced degrees in health communication and know how to tackle cognitive biases and identify barriers that can prevent members from closing HEDIS gaps. Our outreaches get results for a reason – they’re scientifically-based!
[i] Brownlee, S., & Lenzer, J. (2009, November). Does the vaccine matter? The Atlantic. Retrieved from https://www.theatlantic.com/magazine/archive/2009/11/does-the-vaccine-matter/307723 [ii] Mayo, A.M., & Cobler, S. (2004). Flu vaccines and patient decision making: What we need to know. Journal of the American Association of Nurse Practitioners, 16(9), 402-410. doi: 10.1111/j.1745-7599.2004.tb00390.x
[iii] Sherman, D.K., & Cohen, G.L. (2002). Accepting threatening information: Self-affirmation and the reduction of defensive biases. Current Directions in Psychological Science, 11(4), 119-123. doi: 10.1111/1467-8721.00182
[iv] Chen, F., & Stevens, R. (2016). Applying lessons from behavioral economics to increase flu vaccination rates. Health Promotion International, 32(6), 1067-1073. doi: 10.1093/heapro/daw031