Psychological Inoculation Improves Resilience against Misinformation on Social Media

"...confirms that inoculation videos could be run as public-service ads ahead of potentially harmful content and thereby easily scaled across millions of users...in a wide range of issue domains..."

Online misinformation continues to have adverse consequences for society. For instance, belief in misinformation about COVID-19 has been linked to reduced willingness to get vaccinated against the disease and lower intentions to comply with public health measures. Inoculation theory, which follows a medical immunisation analogy and posits that it is possible to build psychological resistance against unwanted persuasion attempts, has been put forward as a way to reduce susceptibility to misinformation, but there are questions about its scalibility on social media. Thus, this group of researchers developed 5 short videos that inoculate people against manipulation techniques commonly used in misinformation and conducted 7 preregistered studies to test them.

The 5 videos, which may be viewed here (with one example, below), pinpoint the following common misinformation techniques: (i) using emotionally manipulative rhetoric to evoke outrage, anger, or other strong emotions, (ii) using incoherent or mutually exclusive arguments, (iii) presenting false dichotomies or dilemmas (24), (iv) scapegoating individuals or groups, and (v) engaging in ad hominem attacks (attacks on an opponent's character). Each 1.5-minute video follows the inoculation procedure by first providing a forewarning of an impending misinformation attack, then issuing a preemptive refutation of the manipulation technique used in the attack, and finally presenting a "microdose" of misinformation in the form of humorous, nonpolitical, and fictitious examples.

To test the videos, the researchers conducted: 5 randomised controlled studies (studies 1 to 5; total n = 5,416, national quota samples of the United States); a replication of the emotional language study with randomised outcome measure response order (study 6, n = 1,068); and an ecologically valid field study where the researchers ran 2 of the videos as an ad campaign on YouTube (study 7, n = 22,632).

In studies 1 to 6, participants were randomly assigned to watch either one of the 5 inoculation videos or a neutral control video of approximately equal length. After watching a video, participants rated 10 synthetic social media posts (mimicking Twitter and Facebook). Each post was randomly either manipulative (i.e., it made use of a manipulation technique) or a neutral counterpart. Participants saw an average of 5 manipulative and 5 neutral stimuli, although this varied per participant because randomisation took place at the stimuli level.

Studies 1-5 found that watching an inoculation video improves people's ability to recognise manipulation techniques in social media content and increases their confidence in their ability to do so. In addition, the videos improve people's ability to distinguish trustworthy and untrustworthy content, as well as the quality of their sharing decisions (i.e., they are either less likely to share manipulative content with others or more likely to share neutral/non-manipulative content).

Study 6 had two goals: (i) to replicate the findings from study 1 (using the emotional language video) 1 year after it was originally conducted and (ii) to check whether manipulating the order in which participants respond to the outcome measures for each of the stimuli (technique recognition, trustworthiness, and sharing) influences the results. Study 6 replicated the main results from study 1, also finding that indicating that varying the response order of the outcome measures beneath the stimuli does not meaningfully influence the results.

Study 7 focused on 2 of the inoculation videos (emotional language and false dichotomies) as advertisement campaigns on YouTube, which can be described as an environment in which people are regularly exposed to false or manipulative content. YouTube does not make behavioural data publicly available; the field study therefore focused on reducing misinformation susceptibility (rather than behavioural measures such as sharing behaviour). As part of this study, around 967,000 YouTube users watched one of the inoculation videos. The treatment group was shown one of the 2 inoculation videos as a YouTube ad. At some point within 24 hours after watching the ad, a random 30% of this group was shown one single-item test question embedded within the YouTube environment, which consisted of a headline containing a particular manipulation technique (the headlines were adapted from the stimuli used in studies 1 and 3). Participants were asked which (if any) manipulation technique the headline contained. The researchers found that the technique-based approach tested here boosted manipulation technique recognition by about 5% on average, though the researchers narrowly failed to reach their preregistered smallest effect size of interest.

In short, studies 1-7 show that the innoculation videos improve manipulation technique recognition, boost confidence in spotting these techniques, increase people's ability to discern trustworthy from untrustworthy content, and improve the quality of their sharing decisions. These effects are robust across the political spectrum and a wide variety of covariates, providing "evidence that these videos are effective not only in a laboratory setting but also 'in the wild' on a video sharing platform and can therefore be easily implemented at scale to improve resilience against misinformation at a cost of about [US]$0.05 per video view." The researchers conclude that these findings are "a significant step forward in our understanding of individual susceptibility to online misinformation and how to prevent people from being misled."