The online test consisted of 4 components:

COMPONENT 1: Gullibility test

COMPONENT 2: Click-bait button

COMPONENT 3: Conspiracy Mentality Questionnaire

COMPONENT 4: Generic conspiracist beliefs scale

All components, items and scales used the original wording in English, as reported by the respective researchers, and translations into Bulgarian, Czech, Italian, Dutch/Flemish and Slovenian, produced by the researchers on the InTACT project's team. Where individual items needed to be replaced (e.g. in Component 4), we kept the text style as close to the original as possible.

COMPONENT 1: Gullibility test ¹

This component is based on the 12-item Gullibility scale (Teunisse et al., 2020). We used the original setup of the test, with a 7-point Likert-scale (from 1=strongly disagree to 7=strongly agree).

Each test item is part of one of two factors:

1. Persuadability;
2. Insensitivity to Untrustworthiness Cues.

COMPONENT 2: Click-bait button

This component is an experimental addition to the test and is based on an idea by [reference] who, as a control mechanism for other conspiracy-related questions, explored a test setting where subjects were asked to subscribe to a fictitious newsletter. In our case we carefully framed a statement asking the subjects to click a button if they wished to quickly access information on some sensational conspiracy theory-framed topic. We we recorded the number of clicks on a non-functional button to measure the eagerness to access such information.

COMPONENT 3: Conspiracy Mentality Questionnaire ²

This component is based on the Conspiracy Mentality Questionnaire (Bruder et al., 2013). It is a 5-item questionnaire where respondents are asked to indicate the level to which they agree with the statement in the item. The level of agreement is measured on a 10-point Likert scale (from 0% = certainly not to 100% = certain), in 10% increments.

We used the original setup of the questionnaire.

COMPONENT 4: Generic conspiracist beliefs scale ³

This part of the test is based on the generic conspiracist belief scale (Bridgerton et al., 2013) and features 5 dimensions:

1. GM - belief in routine governmental malfeasance;
2. MG - belief in the existence of malevolent global conspiracies;
3. ET - belief in the existence and cover-up of extraterrestrials;
4. CI - concerns over the unethical control of information;
5. PW - belief in conspiracies infringing on people's well-being and liberty.

The original study has a list of 75 items, and there is a shortened version of 15 items (3 per dimension). We used the short version and adapted the individual items to achieve a better fit with our assessment of the predominant and shared conspiracy theories in the countries where the InTACT Benchmark test was used.

The answers are collected via a 5-point Likert scale with a qualitative label associated with each point (1: definitely not true; 2: probably not true; 3: not sure/cannot decide; 4: probably true; 5: definitely true).

References:

1. Teunisse, A. K., Case, T. I., Fitness, J., & Sweller, N. (2020). I Should Have Known Better: Development of a Self-Report Measure of Gullibility. Personality and Social Psychology Bulletin, 46(3), 408–423. https://doi.org/10.1177/0146167219858641
2. Bruder, Martin & Haffke, Peter & Neave, Nick & Nouripanah, Nina & Imhoff, Roland. (2013). Measuring Individual Differences in Generic Beliefs in Conspiracy Theories Across Cultures: Conspiracy Mentality Questionnaire. Frontiers in Psychology. 4. 225. 10.3389/fpsyg.2013.00225. https://www.researchgate.net/publication/236615234
3. Brotherton R, French CC and Pickering AD (2013) Measuring belief in conspiracy theories: the generic conspiracist beliefs scale. Front. Psychol. 4:279. doi: 10.3389/fpsyg.2013.00279. https://www.frontiersin.org/articles/10.3389/fpsyg.2013.00279