Science deniers question scientific milestones and spread misinformation, contradicting decades of scientific endeavour. Advocates for science need effective rebuttal strategies and are concerned about backfire effects in public debates. We conducted six experiments to assess how to mitigate the influence of a denier on the audience. An internal meta-analysis across all the experiments revealed that not responding to science deniers has a negative effect on attitudes towards behaviours favoured by science (for example, vaccination) and intentions to perform these behaviours. Providing the facts about the topic or uncovering the rhetorical techniques typical for denialism had positive effects. We found no evidence that complex combinations of topic and technique rebuttals are more effective than single strategies, nor that rebutting science denialism in public discussions backfires, not even in vulnerable groups (for example, US conservatives). As science deniers use the same rhetoric across domains, uncovering their rhetorical techniques is an effective and economic addition to the advocates’ toolbox.
Subscribe to Journal
Get full journal access for 1 year
only $8.25 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Vaccines and immunization. World Health Organization http://www.euro.who.int/en/health-topics/disease-prevention/vaccines-and-immunization/vaccines-and-immunization/vaccine-quality,-efficacy-and-safety (2018).
Causes of Climate Change Climate Action. https://ec.europa.eu/clima/change/causes_en (European Commission, 2018).
Teaching of Evolution: Fact and Theory https://www.acs.org/content/acs/en/policy/publicpolicies/education/evolution.html (American Chemical Society, 2017).
Carmichael, J. T., Brulle, R. J. & Huxster, J. K. The great divide: understanding the role of media and other drivers of the partisan divide in public concern over climate change in the USA, 2001–2014. Clim. Change 141, 599–612 (2017).
Mildenberger, M. & Leiserowitz, A. Public opinion on climate change: is there an economy–environment tradeoff? Env. Polit. 26, 801–824 (2017).
Lewandowsky, S., Ecker, U. K. H. & Cook, J. Beyond misinformation: understanding and coping with the “post-truth” era. J. Appl. Res. Mem. Cogn. 6, 353–369 (2017).
Chigwedere, P., Seage, G. R., Gruskin, S., Lee, T.-H. & Essex, M. Estimating the lost benefits of antiretroviral drug use in South Africa. J. Acquir. Immune Defic. Syndr. 49, 410–415 (2008).
Flaherty, D. K. The vaccine-autism connection: a public health crisis caused by unethical medical practices and fraudulent science. Ann. Pharmacother. 45, 1302–1304 (2011).
Lewandowsky, S., Ballard, T., Oberauer, K. & Benestad, R. A blind expert test of contrarian claims about climate data. Glob. Environ. Change 39, 91–97 (2016).
Björnberg, K. E., Karlsson, M., Gilek, M. & Hansson, S. O. Climate and environmental science denial: a review of the scientific literature published in 1990–2015. J. Clean. Prod. 167, 229–241 (2018).
Dunlap, R. E. Climate Change skepticism and denial: An introduction. Am. Behav. Sci. 57, 691–698 (2013).
Ziman, J. Is science losing its objectivity? Nature 382, 751–754 (1996).
Diethelm, P. & McKee, M. Denialism: what is it and how should scientists respond? Eur. J. Public Health 19, 2–4 (2009).
Lewandowsky, S. & Oberauer, K. Motivated rejection of science. Curr. Dir. Psychol. Sci. 25, 217–222 (2016).
Hornsey, M. J. & Fielding, K. S. Attitude roots and jiu jitsu persuasion: understanding and overcoming the motivated rejection of science. Am. Psychol. 72, 459–473 (2017).
Oreskes, N. & Conway, E. M. Defeating the merchants of doubt. Nature 465, 686–687 (2010).
Betsch, C. Advocating for vaccination in a climate of science denial. Nat. Microbiol. 2, 17106 (2017).
Williamson, P. Take the time and effort to correct misinformation. Nature 540, 171 (2016).
Cockrell, M., Dubickas, K., Hepner, M., Ilich, A. & McCarthy, M. Embracing advocacy in science. Fisheries 43, 179–182 (2018).
van der Linden, S., Leiserowitz, A., Rosenthal, S. & Maibach, E. Inoculating the public against misinformation about climate change. Glob. Chall. 1, 1600008 (2017).
Cook, J., Lewandowsky, S. & Ecker, U. K. H. Neutralizing misinformation through inoculation: exposing misleading argumentation techniques reduces their influence. PLoS One 12, e0175799 (2017).
Lewandowsky, S., Ecker, U. K. H., Seifert, C. M., Schwarz, N. & Cook, J. Misinformation and its correction: continued influence and successful debiasing. Psychol. Sci. Public Interest 13, 106–131 (2012).
Ecker, U. K. H., Hogan, J. L. & Lewandowsky, S. Reminders and repetition of misinformation: helping or hindering its retraction? J. Appl. Res. Mem. Cogn. 6, 185–192 (2017).
Schmid, P., MacDonald, N. E., Habersaat, K. & Butler, R. Commentary to: how to respond to vocal vaccine deniers in public. Vaccine 36, 196–198 (2018).
Benoit, W. L., Hansen, G. J. & Verser, R. M. A meta-analysis of the effects of viewing U.S. presidential debates. Commun. Monogr. 70, 335–350 (2003).
Vosoughi, S., Roy, D. & Aral, S. The spread of true and false news online. Science 359, 1146–1151 (2018).
Seiter, J., Weger, H., Jensen, A. & Kinzer, H. The role of background behavior in televised debates: does displaying nonverbal agreement and/or disagreement benefit either debater? J. Soc. Psychol. 150, 278–300 (2010).
Nyhan, B. & Reifler, J. Does correcting myths about the flu vaccine work? An experimental evaluation of the effects of corrective information. Vaccine 33, 459–464 (2015).
Nyhan, B. & Reifler, J. When corrections fail: the persistence of political misperceptions. Polit. Behav. 32, 303–330 (2010).
Cook, J. & Lewandowsky, S. Rational irrationality: modeling climate change belief polarization using Bayesian networks. Top. Cogn. Sci. 8, 160–179 (2016).
Best Practice Guidance: How to Respond to Vocal Vaccine Deniers in Public (World Health Organization Regional Office for Europe, 2016).
Cacioppo, J. T., Petty, R. E. & Morris, K. J. Effects of need for cognition on message evaluation, recall, and persuasion. J. Pers. Soc. Psychol. 45, 805–818 (1983).
Friestad, M. & Wright, P. The persuasion knowledge model: how people cope with persuasion attempts. J. Consum. Res. 21, 1–31 (1994).
Pornpitakpan, C. The persuasiveness of source credibility: a critical review of five decades’ evidence. J. Appl. Soc. Psychol. 34, 243–281 (2004).
Chaiken, S. Heuristic versus systematic information processing and the use of source versus message cues in persuasion. J. Pers. Soc. Psychol. 39, 752–766 (1980).
Hronikx, J. A review of experimental research on the relative persuasiveness of anecdotal, statistical, causal, and expert evidence. Stud. Commun. Sci. 5, 205–216 (2005).
Allen, M. Meta‐analysis comparing the persuasiveness of one‐sided and two‐sided messages. West. J. Speech Commun. 55, 390–404 (1991).
O’Keefe, D. J. How to handle opposing arguments in persuasive messages: a meta-analytic review of the effects of one-sided and two-sided messages. Ann. Int. Commun. Assoc. 22, 209–249 (1999).
Cook, J. & Lewandowsky, S. The Debunking Handbook (University of Queensland, 2011).
Petty, R. E. & Cacioppo, J. T. The elaboration likelihood model of persuasion. Adv. Exp. Soc. Psychol. 19, 123–205 (1986).
Eisend, M. Understanding two-sided persuasion: an empirical assessment of theoretical approaches. Psychol. Market. 24, 615–640 (2007).
Sheeran, P. et al. The impact of changing attitudes, norms, and self-efficacy on health-related intentions and behavior: a meta-analysis. Health Psychol. 35, 1178–1188 (2016).
O’Keefe, D. J. Persuasion: Theory and Research (Sage, 2002).
O’Keefe, D. J. Message generalizations that support evidence-based persuasive message design: specifying the evidentiary requirements. Health Commun. 30, 106–113 (2015).
Goh, J. X., Hall, J. A. & Rosenthal, R. Mini meta-analysis of your own studies: some arguments on why and a primer on how. Soc. Personal. Psychol. Compass 10, 535–549 (2016).
Baguley, T. Standardized or simple effect size: what should be reported? Br. J. Psychol. 100, 603–617 (2009).
Cohen, P., Cohen, J., Aiken, L. S. & West, S. G. The problem of units and the circumstance for POMP. Multivar. Behav. Res. 34, 315–346 (1999).
Leys, C., Ley, C., Klein, O., Bernard, P. & Licata, L. Detecting outliers: do not use standard deviation around the mean, use absolute deviation around the median. J. Exp. Soc. Psychol. 49, 764–766 (2013).
Anderson, T Communicating science-based messages on vaccines. Bull. World Health Organ. 95, 670–671 (2017).
van der Linden, S., Leiserowitz, A. & Maibach, E. Scientific agreement can neutralize politicization of facts. Nat. Hum. Behav. 2, 2–3 (2018).
Cook, J., Maibach, E., van der Linden, S. & Lewandowsky, S. The Consensus Handbook (Climate Change Communication, 2018).
Nsangi, A. et al. Effects of the informed health choices primary school intervention on the ability of children in Uganda to assess the reliability of claims about treatment effects: a cluster-randomised controlled trial. Lancet 390, 374–388 (2017).
Sheeran, P. Intention—behavior relations: a conceptual and empirical review. Eur. Rev. Soc. Psychol. 12, 1–36 (2002).
Berinsky, A. J., Margolis, M. F. & Sances, M. W. Separating the shirkers from the workers? Making sure respondents pay attention on self-administered surveys. Am. J. Polit. Sci. 58, 739–753 (2014).
Oreskes, N. Beware: transparency rule is a Trojan horse. Nature 557, 469 (2018).
EFS Survey, v. Spring 2016–Winter 2018 (Questback GmbH, 2016).
Schmid, P. & Betsch, C. Effective strategies for rebutting science denialism in public discussions. Preprint at OSF https://doi.org/10.17605/OSF.IO/XX2KT (2019).
Sedgwick, P. Meta-analyses heterogeneity and subgroup analysis. BMJ 346, f4040 (2013).
The authors thank B. Wippert, T. Steinke, J. Gerlach and M. Schwarzer for their help collecting the data and developing the stimulus material and L. Korn for support visualizing Fig. 2 and Supplementary Fig. 2. The authors are also grateful for the valuable input from K. Habersaat. Parts of the study were funded by grants to C.B. from the German Federal Ministry for Education and Research (BMBF) via the interdisciplinary and trans-sectoral consortium InfectControl2020 to the University of Erfurt (no. 03ZZ0819A) and the German Research Foundation to C.B. (no. BE3970/11-1). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. No other funding bodies were involved.
The authors declare no competing interests.
Peer review information: Primary Handling Editor: Aisha Bradshaw.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Schmid, P., Betsch, C. Effective strategies for rebutting science denialism in public discussions. Nat Hum Behav 3, 931–939 (2019). https://doi.org/10.1038/s41562-019-0632-4
Pro-Science, Anti-Science and Neutral Science in Online Videos on Climate Change, Vaccines and Nanotechnology
Media and Communication (2020)
Inland Waters (2020)
ACCESS: Contemporary Issues in Education (2020)