Like the flu shot, message inoculation won't last forever
Just as influenza vaccines employ a weakened virus to stimulate the immune system and produce antibodies against the real thing during flu season, message inoculation – with a weakened form of the other side's argument – should arm the public with anti-baloney sentiments against persuasive messages in the future.
That's according to communication scholars who first proposed inoculation theory in the heyday of advertising's "Mad Men" in 1964.
In 2012, "we tried an online experiment with message inoculation and the debate over soda taxes," says Jeff Niederdeppe, associate professor of communication in Cornell's College of Agriculture and Life Sciences. "Inoculation to sway public opinion can work. But like the flu shot, it's not forever."
Researchers from Cornell, Johns Hopkins University and the University of Minnesota recently published their results in a paper titled "Inoculation in Competitive Framing: Examining Message Effects on Policy Preferences" (Public Opinion Quarterly, online Aug. 25). Experimental subjects received nearly as many combinations of anti- and pro-tax messages (communication researchers call them "frames") as there are soda pop varieties on the grocery store shelf.
In some cases, the volume of anti-tax framing was in proportion to anti-tax advertising in states where taxes on sugary soda had been proposed (and failed). Big soda companies have more publicity resources than health-advocacy groups, the researchers noted.
Inoculation took the form of weakened anti-tax messaging – sometimes combined with information on the motives of soda companies (called source derogation) – and warnings that stronger anti-tax messages might be coming.
And inoculation really worked – for a while. Many experimental subjects were more favorably inclined toward paying a penny-per-ounce tax on sugary soda beverages if that would curb the obesity epidemic in this country. And many were more suspicious of the powerful beverage industry.
But with the passage of time (seven days) and renewed exposure to more powerful anti-tax framing, minds changed. That's what happened in eight states where voters or legislators considered sugar taxes in 2012.
"Exposure to strong oppositional frames at follow-up canceled out the initial persuasive effects of the inoculation message and thus failed to produce a net increase in policy support," the researchers concluded.
A "booster shot" of pro-tax messaging failed to keep anti-tax messages from moving people further against the tax. Even where soda tax advocates tried to use message inoculation and derogation against anti-tax forces, those meagerly financed efforts were overwhelmed.
Score one for communication theory. "Results offer new directions for the study of message strategy and effects in asymmetric, competitive framing contests, a situation characterizing the information environment about many U.S. policy issues," the authors added.
A proposed soda tax (two cents an ounce) is on the ballot for San Francisco voters in November. The arguments and counterarguments Niederdeppe is hearing in the local media sound very familiar, he says.
Last year's flu vaccine might not help this season if influenza viruses mutate to outwit previous vaccines. Immune system antibodies might not recognize this year's model.
Eight states considered soda taxes in 2012: Hawaii, Illinois, Indiana, Mississippi, Rhode Island, Tennessee, Vermont and West Virginia. Campaigns against soda taxes rarely mention the names of soda companies as sponsors. Savvy voters with finely tuned anti-baloney radar might suspect messages from the American Beverage Association, which indeed is sponsored by Big Soda.
But who would guess an outfit called Americans Against Food Taxes is anything but wholesome?