A PR I L . 1 5 . 2 0 1 5

HOW TO COMBATMISINFORMATION

ON VACCINES & OTHER PUBLIC HEALTH ISSUES

WILLAM D. LEACH, PHDSOL PRICE SCHOOL OF PUBLIC POLICY

UNIVERSITY OF SOUTHERN CALIFORNIA

USC Provost ProfessorNorbert Schwarz studies thepsychology of meta­cognition– meaning our thoughts aboutwhat we think and why – andit's application to harmfulmisconceptions about healthand well­being.

Drawing upon a decade of research, this presentation reviews whystandard myth­busting campaigns backfire, and what we should doinstead to combat harmful health myths while communicatingaccurate health information.

Truth-Testing HeuristicsPeople are more likely to believe new information if it satisfiesfive metacognitive criteria:

1. Compatibility: Is it compatible with other things I know?2. Coherence: Is it an internally coherent and plausible story?3. Credibility: Does it come from a credible source?4. Corroboration: Is there a lot of supporting evidence?5. Consensus: Do others believe this?

Eight Communication Strategies forEffective Public Health Campaigns

Take­home messages from research on metacognition aresummarized in the following eight communication strategies.

#1Do not repeat misinformation.

“False information is better left alone. Anyattempt to explicitly discredit false information

necessarily involves a repetition of the falseinformation, which may contribute to its later

familiarity and acceptance” (Schwarz et al. 2007).Therefore, to fight misinformation on vaccines, itis best to ignore the misinformants, and instead

focus on communicating the risks of preventableinfections and the benefits of vaccination.

#2Repeat “true facts” often.

Repetition increases familiarity and implies that aclaim is widely accepted. Ideally, multiple crediblesources should repeat the same information, but

failing that, simply having the same authority repeatthe same message increases perceptions of

consensus and veracity (Schwarz 2015).

#3Enlist credible sources.

Heuristic #3 highlights the importance of credibility.However, highly credible sources should be especiallycareful not to repeat a myth. People may later associate

the myth with the credible source, but forget that theinformation is untrue.

#4Lead with a disclaimer.

If misinformation must be repeated, explicitly warn theaudience ahead of time that they are about to hear something

that merits skepticism. The best protection against harmfulhealth misconceptions is suspicion when you first hear it. Forexample, the FDA requires that labels for dietary supplements

include the disclaimer, “This product is not intended todiagnose, treat, cure, or prevent any disease.” Moving this

message to the top of label and the beginning of radioadvertisements would enhance its impact.

#5Emphasize consensuson the true information.

Heuristic #5 implies one should emphasize consensuson true information and avoid signaling consensus onfalse information. News reports on health myths, such

as the unfounded link between childhood vaccinesand autism, unavoidably normalize mistaken beliefs

by suggesting they are commonly held.

#6Make the message simple,

brief, and memorable.Simple fonts, clear language, brevity, and white space on

the page help the audience feel as though they understandthe message effortlessly. Rhymes, jingles, mnemonics,and visuals make a message memorable. “If the myth is

simpler and more compelling than your debunking, it willbe cognitively more attractive” (Lewandowsky et al. 2012).

#7Affirm the audience's worldview.

People rarely accept new information that contradicts theirexisting beliefs. To soften resistance, validate the audience’sbasic values. For example, people who fear childhood vacci­nation and distrust the government or the pharmaceuticalindustry might be more receptive to vaccine information

from an independent non­profit organization dedicated tochildren’s health, especially if vaccination is framed as avoluntary action taken by thoughtful parents who have

thoroughly investigated the pros and potential cons.

#8Nudge toward better decisions.

Policymakers can often design “choice architecture” so thatpeople automatically gravitate toward the preferred decision.A promising example from behavioral economics is the use of

defaults . For example, many people never skip a six­month dentalcheck­up, largely because dental offices always schedule your

next visit before you leave the office. If family physicians routinelycalendared their patients’ annual flu vaccine, vaccination rates

might rise accordingly. Flipping the default choice would improvepublic health without altering patients’ basic options and without

confronting misinformation about vaccines.

GET THE FULL STORY AT USC'S

Executive Master's of Health Administration

http://exechealthadmin.usc.edu/blog