Delusional Ideation, Jumping to Conclusions, and Conspiracist Beliefs: An Exploratory Study in a Non-Clinical Hong Kong Sample

Conspiracy beliefs have been linked to psychosis-like cognitive-perceptual traits, but less is known about whether they are associated with the jumping-to-conclusions (JTC) reasoning bias. This exploratory cross-sectional study examined whether delusional ideation and JTC were associated with conspiracist beliefs in a non-clinical convenience sample of 54 young people in Hong Kong (aged 13–26 years; mostly students). Participants completed a single-trial 60:40 beads task, the 21-item Peters et al. Delusions Inventory, and a 38-item Conspiracy Theory Questionnaire. Fewer draws to decision indicated stronger JTC. Delusional ideation was positively associated with conspiracist beliefs, r = .55, 95% CI [.33, .71], and was associated with 30% of the variance in conspiracist-belief scores. Draws to decision were not significantly correlated with conspiracist beliefs, r = .15, 95% CI [−.12, .41], or with delusional ideation, r = −.16, 95% CI [−.41, .11]. When both predictors were entered simultaneously, delusional ideation remained robustly associated with conspiracist beliefs, whereas a small positive coefficient for draws to decision (opposite in direction to the JTC hypothesis) was not robust across sensitivity analyses. Because the sample provided 80% power only for correlations of about .37 or larger, small-to-moderate associations involving JTC cannot be ruled out. The findings replicate the link between delusion-proneness and conspiracist belief but provide no evidence for an association between neutral probabilistic data gathering and conspiracist ideation. Larger preregistered studies using multiple reasoning tasks are needed.