Jumping to Conclusions Is Associated with Paranoia but Not General Suspiciousness: A Comparison of Two Versions of the Probabilistic Reasoning Paradigm

Table 1

Demographic, psychopathological, and experimental characteristics of the two samples. Percentages, means, and standard deviations (in brackets).

	Traditional variant (n = 961)	Extended variant (n = 938)	Statistics
Demographics
Gender (female/male)	61%/39%	60%/40%	χ ^2(1) = 0.74; P > .7
Age in years	43.15 (15.72)	43.00 (15.12)	t(1897) = 0.24; P > .8
Educational level (below 13th grade/13th  grade/university degree)	35%/27%/38%	37%/26%/37%	χ ^2(1) = 0.29; P > .8
Paranoia Checklist
Total score	26.44 (11.67)	26.88 (11.32)	t(1897) = 0.82; P > .4
Unspecific suspiciousness (regression score;  see factor analysis)	−.02 (1.00)	.02 (.99)	t(1897) = 0.81; P > .4
Psychotic paranoia (regression score)	−.00 (1.01)	.01 (.99)	t(1897) = 0.29; P > .7
Probabilistic reasoning
JTC (1st fish)	37%	66%	χ ^2(1) = 163.98; P < .001
JTC (1st or 2nd fish)	52%	74%	χ ^2(1) = 99.63; P < .001
Draws to decision	3.13 (2.56)	2.18 (2.29)	t(1897) = 8.49; P < .001
Decision threshold in %	—	73.93% (19.56)	—

Note. JTC: jumping to conclusions.