Who Would YOU Listen To?
Who do YOU think would be more influential in persuading people to support vaccination against the human papillomavirus—a scourge that causes cervical cancer and thousands of deaths each year?
Most people would guess the authoritative-looking woman doctor on the left. After all, how much influence could a non-expert like the Middle School student on the right be expected to wield?
That was the focus of my study of spokesperson expertise.
Universal HPV vaccination would save more than 3,000 lives annually in the United States, and more than 350,000 worldwide. It makes sense. Its benefits seem almost inarguable. But there is a huge amount of opposition, largely distributed along political and ideological lines.
This is the intersection of health, science and politics. Mistrust and disbelief in evidence-based science and the recommendations of scientists are widespread and distributed along partisan lines.
It is hard to prove any immediate life-and-death consequences to rejection of evolution or denial of the possibility of human agency in climate change. But with HPV and cervical cancer, the consequences are clear, present and immediate. We can document that partisan opposition to HPV vaccination is killing people right now.
The results of my study suggest that people who are inclined to oppose HPV vaccination are more likely to listen to pro-vaccination messages from an obviously non-expert spokesperson (in this study, an innocent-looking middle school student) than from an expert (in this study, an authoritative-looking woman doctor).
In my study, 474 adults were randomly divided into three groups. One group was instructed to read some basic, neutral information about the HPV virus and a pro-vaccination advocacy message attributed to the woman doctor.
A second group was instructed to read the same basic information about the HPV virus and the same pro-vaccination advocacy message, but for this group the message was attributed to the middle school student.
The third group read the same basic information about the HPV virus, but received no advocacy message. Members of all three groups were also instructed to rate themselves politically as either Progressive, Centrist or Conservative.
After completing their reading assignments, the subjects were surveyed about their attitudes toward HPV vaccination.
The attitude-scores of the control group (the ones who read only basic information but received no advocacy message) showed how favorability toward HPV vaccination is skewed along partisan political lines. The more conservative the individual, the more opposed to HPV vaccination that person was likely to be.
Displaying the results for all three groups side-by-side (see chart below), it is clear that Centrists and Conservatives—those more likely to be opposed to vaccination—are more positively influenced by the Non-Expert spokesperson than the Expert.
For both Centrists and Conservatives, attitudes among those who read the advocacy message from the Non-Expert were significantly more positive than among those who received no advocacy message. There was no such significant difference in attitudes of those who read the advocacy message attributed to the Expert.
With Centrists, in fact, attitudes toward vaccination among those who received the advocacy message delivered by the Expert were virtually identical to those who received no advocacy message at all.
Among Progressives — who tend to favor HPV vaccination to begin with — attitudes toward HPV vaccination were more more positively influenced by the Expert than the Non-Expert.
Since virtually all pro-vaccination campaigns are spearheaded by people who favor vaccination, it seems likely that the tendency to rely on expert authorities as public advocates for vaccination may be the result of unexamined and untested assumptions that what influences Progressives will influence everyone.