A comparison of jumping to conclusion bias between patients with paranoid schizophrenia, non-paranoid schizophrenia or anxiety disorder and healthy i̇ndividuals

Introduction and Aim: Patients with delusions reach a conclusion by using less information in uncertain conditions. This is called "jumping to conclusion bias". In this thesis, it is aimed to compare jumping to conclusion bias between patients with paranoid schizophrenia, non-paranoid schizophrenia or anxiety disorder and healthy individuals. Additionally, we aim to discover the factors that influence jumping to conclusion bias. Material and Methods: 35 patients with paranoid schizophrenia, 31 patients with non-paranoid schizophrenia, 31 patients with anxiety disorder and 31 healthy volunteers were included in this study. Firstly, the sociodemographic characteristics of all participants were recorded, then, KBT, LKT, BPRS, SANS, HAM-D, HAM-A and BIS-11 scales were performed. Patients with schizophrenia were also evaluated with SAPS and CDO scales. Results: Patients with paranoid schizophrenia made decisions after drawing fewer beads than patients in the control group in KBT 60/40 (F(3-124)=3.495, p<.05). There was significancy concerning the KBT 90/10 JTC (X 2=8.989, p<.05) and KBT 60/40 JTC (X2=9.394, p<.05) between the paranoid schizophrenia patient group and the healthy group. Moreover, in the paranoid schizophrenia group, those patients who had jumping to conclusion bias (median=21.29) had significantly higher total delusions scores than patients (mean= 14.71) who had no jumping to conclusion bias according to the KBT 60/40 version. When the factors that influence JTC bias were researched in the paranoid schizophrenia group, it was determined that JTC bias was increased if total SANS and age were increased and if HAM-A and academic year were decreased in the KBT 90/10 version. However, in the KBT 60/40 version, if the total SAPS, BIS-NP and age were increased and BIS-M was decreased JTC bias was found to be increased. Conclusion: Patients with paranoid schizophrenia have more JTC bias than healthy people. Additionally, in this group, it was seen that JTC bias is increased in relation to an increase in delusions severity. There are other factors that influence JTC bias change if the conditions are changed. Negative symptoms influence JTC bias in more certain conditions, whereas positive symptoms influence in more uncertain conditions. Moreover, impulsivity can be said to influence JTC bias. If long term studies about the effects of JTC bias on the prognosis and treatments of psychotic disorders are performed then we should have a better understanding of JTC bias.