Measuring belief in conspiracy theories

Dans cet article nous présentons d'une part la validation d'une échelle de croyance aux théories du complot en un item (en français et en anglais), d'autre part nous présentons la traduction en français d'autres échelles classiques de croyance aux théories du complot.

We designed, in French and in English, a single-item scale to measure people’s general tendency to believe in conspiracy theories. The validity and reliability of this scale was assessed in 3 studies (total N = 555). In Study 1 (N = 152), positive correlations between the single-item scale and 3 other conspiracy belief scales on a French student sample suggested good concurrent validity. In Study 2 (N = 292), we replicated these results on a larger and more heterogeneous Internet American sample. Moreover, the scale showed good predictive validity—responses predicted participants’ willingness to receive a bi-monthly newsletter about alleged conspiracy theories. Finally, in Study 3 (N = 111), we observed good test-retest reliability and demonstrated both convergent and discriminant validity of the single-item scale. Overall these results suggest that the single-item conspiracy belief scale has good validity and reliability and may be used to measure conspiracy belief in favor of lengthier existing scales. In addition, the validation of the single- item scale led us to develop and start validating French versions of the Generic Conspiracist Beliefs scale, the Conspiracy Mentality Questionnaire, and a 10-item version (instead of the 15-item original version) of the Belief in Conspiracy Theories Inventory.

Lantian, A., Muller, D., Nurra, C., & Douglas, K. (2016). Measuring Belief in Conspiracy Theories: Validation of a French and English Single-Item Scale. International Review of Social Psychology, 1, 1-14. (pdf)