, supporting findings in the literature that misinformation tends to linger in the memory and efforts to dislodge it may in fact reinforce it.
In a study of 120 students recruited from diverse departments of the University of Edinburgh, the Suor Orsola Benincasa University of Naples, and the Second University of Naples, 61% were women, and the mean age was 25 years. Most students had a bachelor’s (38%) or master’s degree (53%), while 11 were PhD students, reported Sara Pluviano, PhD, of the University of Edinburgh, and her associates.
The participants completed a baseline questionnaire assessing their beliefs and attitudes about immunization, and twice completed a questionnaire that had focused on general misperceptions about vaccines causing autism, vaccine side effects, and how likely they would be to give MMR vaccine to their children – immediately after an intervention and after a 7-day delay.
Students were exposed to one of four correction interventions.
In the first, participants were given a booklet confronting 10 “myths” with a number of “facts” about vaccines (myths vs. facts group). In the second, students were presented with a series of tables comparing the potential problems caused by measles, mumps, and rubella with the potential side effects caused by the MMR vaccine (graphics group). In the third intervention, participants were shown photos of unvaccinated children with measles, mumps, and rubella, in addition to the symptoms of each disease and warnings about vaccinating one’s own child (fear group). The fourth was the control condition, where participants were given two unrelated fact sheets with tips to help prevent medical errors and get safer health care (control group).
“The myths vs. facts format, at odds with its aims, induced stronger beliefs in the vaccine/autism link and in vaccines side effects over time, lending credit to the literature showing that countering false information in ways that repeat it may further contribute to its dissemination,” the researchers said. Also, “the exposure to fear appeals through images of sick children led to more increased misperceptions about vaccines causing autism. Moreover, this corrective strategy induced the strongest beliefs in vaccines side effects.
“The usage of fact/icon boxes resulted in less damage but did not bring any effective result,” they said.
“Our pattern of results thus confirms that there should be more testing of public health campaign messages,” Dr. Pluviano and her associates cautioned. “This is especially true because corrective strategies may appear effective immediately, yet backfire even after a short delay when the message they tried to convey gradually fades from memory, allowing common misconceptions to be more easily remembered and identified as true.”
Read more in PLOS One (2017 Jul 27. doi: 10.1371/journal.pone.0181640).