Climate Change and Covid-19: Testing for Motivated Reasoning

Last registered on January 11, 2022


Trial Information

General Information

Climate Change and Covid-19: Testing for Motivated Reasoning
Initial registration date
January 11, 2022

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
January 11, 2022, 9:19 AM EST

First published corresponds to when the trial was first made public on the Registry after being reviewed.



Primary Investigator

RWI - Leibniz Institute for Economic Research

Other Primary Investigator(s)

Additional Trial Information

In development
Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
With climate change and the Covid-19 pandemic the world currently faces two dominant challenges that differ in their psychological distance and exhibit a wide public divide. One explanation for this divide is motivated reasoning. In this study, we shed light on the role of motivated reasoning in the context of climate change as well as the Covid-19 pandemic and try to disentangle directional and accuracy motivated reasoning. To this end, we conduct a large-scale survey among roughly 6,000 individuals in Germany and embed a treatment that is desinged to encourage accuracy seeking. In addition, we elicit a wide range of personality traits and attitudes toward climate change and the Covid-19 pandemic that allow us to determine the participants' prior beliefs and distinguish between `deniers' and `believers'. In particular, we aim at answering the following research questions: (1) First, to what extent are people directionally and accuracy-motivated? Second, using the psychological characteristics of the need to evaluate, preference for being right, and preference for consistency, as well as our treatment, we ask: Does accuracy seeking lead to less polarization than directional motivated reasoning in terms of (2a) a lower divergence in opinions and (2b) a lower likelihood in believing confirmatory and rejecting contradicting information? (3) Third, we investigate whether motivated reasoning is more prevalent when it comes to climate change or to the Covid-19 pandemic.
External Link(s)

Registration Citation

Sommer, Stephan. 2022. "Climate Change and Covid-19: Testing for Motivated Reasoning." AEA RCT Registry. January 11.
Experimental Details


One third of the respondents receives a treatment that is designed to increase their motivation to accurately assess the online articles presented in the experimental part. Specifically, to these participants we emphasize that it is important to carefully and impartially think about the articles presented, and ask them to justify their assessment of the credibility of the presented articles.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Our main outcome is whether respondents believe the news they face in the experiment.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
Our primary analysis aims at exploring how participants respond to real and fake news on climate change and Covid-19. In particular, we analyze the differential reactions to these news of respondents with a varying degree of skepticism toward climate change or the Covid-19 pandemic. To this end, we design an experiment that randomly confronts participants with four randomly selected online articles on climate change and Covid-19 and embed it in our questionnaire.

In the experimental part of our study, for each of the two topics of climate change and the Covid-19 pandemic, each participant sees two randomly selected online articles, i.e. four articles in total. These articles are selected from a pool of six articles on climate change and five articles on Covid-19. We show the participants screenshots of the original news release and provide the link to the respective website. Afterwards, we will ask several questions on the credibility of the articles presented.
Experimental Design Details
Randomization Method
Randomization by a computer
Randomization Unit
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
6000 individuals
Sample size: planned number of observations
6000 individuals
Sample size (or number of clusters) by treatment arms
4000 individuals in the control group and 2000 individuals in the treatment group
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
IRB Approval Date
IRB Approval Number
Analysis Plan

Analysis Plan Documents


MD5: d2c602d57e818d33e30a0e8c034f6926

SHA1: 724fcc057c9936c3a1f100836a6d6cb95111f02d

Uploaded At: January 11, 2022


Post Trial Information

Study Withdrawal

There is information in this trial unavailable to the public. Use the button below to request access.

Request Information


Is the intervention completed?
Data Collection Complete
Data Publication

Data Publication

Is public data available?

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials