Are deluded people unusually prone to illusory correlation?

This study reexamines the possibility that paranoid individuals are unusually prone to perceive illusory correlations. The authors use emotionally neutral word pairs to examine the illusory correlation phenomenon in three diagnostic groups: nonparanoid schizophrenia (n = 10), paranoid schizophrenia or delusional disorder (n = 9), and depression (n = 10). A one-way analysis of variance shows that the three groups do not differ in their tendency to make illusory correlations. Three separate t tests that compare the data from each of the clinical groups in this study with normative data again reveal no significant difference. The clinical implications of these findings are discussed.