Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Apr 7;117(14):7672-7683.
doi: 10.1073/pnas.1913678117. Epub 2020 Mar 23.

The effects of communicating uncertainty on public trust in facts and numbers

Anne Marthe van der Bles  1   2   3 , Sander van der Linden  1   2   4 , Alexandra L J Freeman  5   2 , David J Spiegelhalter  5   2
Affiliations

The effects of communicating uncertainty on public trust in facts and numbers

Anne Marthe van der Bles et al. Proc Natl Acad Sci U S A. .

Abstract

Uncertainty is inherent to our knowledge about the state of the world yet often not communicated alongside scientific facts and numbers. In the "posttruth" era where facts are increasingly contested, a common assumption is that communicating uncertainty will reduce public trust. However, a lack of systematic research makes it difficult to evaluate such claims. We conducted five experiments-including one preregistered replication with a national sample and one field experiment on the BBC News website (total n = 5,780)-to examine whether communicating epistemic uncertainty about facts across different topics (e.g., global warming, immigration), formats (verbal vs. numeric), and magnitudes (high vs. low) influences public trust. Results show that whereas people do perceive greater uncertainty when it is communicated, we observed only a small decrease in trust in numbers and trustworthiness of the source, and mostly for verbal uncertainty communication. These results could help reassure all communicators of facts and science that they can be more open and transparent about the limits of human knowledge.

Keywords: communication; contested; posttruth; trust; uncertainty.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interest.

Figures

Fig. 1.
Fig. 1.
The results of experiment 1: Means per condition for perceived uncertainty (A), trust in numbers (B), and trust in the source (C). The error bars represent 95% CIs around the means, and jitter represents the distribution of the underlying data.
Fig. 2.
Fig. 2.
The results of experiment 2: Means per condition for perceived uncertainty (A), trust in numbers (B), and trust in the source (C). The error bars represent 95% CIs around the means, and jitter represents the distribution of the underlying data.
Fig. 3.
Fig. 3.
The results of experiment 3: Means per condition for perceived uncertainty (A), trust in numbers (B), and trust in the source (C). The error bars represent 95% CIs around the means, and jitter represents the distribution of the underlying data.
Fig. 4.
Fig. 4.
The results of experiment 4: Means per condition for perceived uncertainty (A), trust in numbers (B), and trust in the source (C). The error bars represent 95% CIs around the means, and the jitter represents the distribution of the underlying data.
Fig. 5.
Fig. 5.
Random-effects metaanalysis. Perceived uncertainty (A), trust in numbers (B), and trust in the source (C).
Fig. 6.
Fig. 6.
Image of the BBC News article that was used in experiment 5 (numerical condition: including a numeric range). Reprinted with permission from BBC News.
Fig. 7.
Fig. 7.
The results of field experiment 5: Means per condition for perceived uncertainty (A), trust in numbers (B), and trust in the source (C). The error bars represent 95% CIs around the means, and the jitter represents the distribution of the underlying data.
See this image and copyright information in PMC

References

    1. Fischhoff B., Communicating uncertainty: Fulfilling the duty to inform. Issues Sci. Technol. 28, 63–70 (2012).
    1. van der Linden S., Löfstedt R. E., Eds., Risk and Uncertainty in a Post-Truth Society (Routledge, 2019).
    1. Edelman, 2018 Edelman Trust Barometer. https://www.edelman.com/research/2018-edelman-trust-barometer. Accessed 5 March 2020.
    1. Edelman, 2017 Edelman Trust Barometer. https://www.edelman.com/research/2017-edelman-trust-barometer. Accessed 5 March 2020.
    1. Pew Research Center, Beyond distrust: How Americans view their government. https://www.people-press.org/2015/11/23/beyond-distrust-how-americans-vi.... Accessed 5 March 2020.

Publication types