title: A comparison of cognitive biases between schizophrenia patients with delusions and healthy individuals with delusion-like experiences.
abstract: BACKGROUND
  The role of psychosis-related cognitive biases (e.g. jumping to conclusions) in a delusion continuum is well-established. Little is known about the role of types of cognitive biases. The aim of this study was to investigate the role of psychosis-related and "Beckian" (i.e. anxiety- and depression-related) cognitive biases assessed with a clinical questionnaire in the delusion continuum and its dimensions.
  
  
  METHODS
  Schizophrenia patients with (n=57) and without (n=35) delusions were compared to healthy subjects who had a low (n=53) and high (n=57) level of delusion-like experiences (DLEs) on the Cognitive Biases Questionnaire for Psychosis (CBQp). Delusion dimensions in the clinical sample were assessed with the semi-structured interview PSYRATS. DLEs were measured with the Peters Delusion Inventory (PDI).
  
  
  RESULTS
  High DLEs participants scored significantly higher than low DLEs, and patients with delusions scored higher than patients without delusions on the total scores of the CBQp. High DLEs participants scored significantly higher than low DLEs on catastrophisation and JTC. Schizophrenia patients with delusions scored significantly higher when compared to patients without delusions on intentionalising, dichotomous thinking, JTC and emotional reasoning. Patients with delusions and high DLEs participants scored similarly on JTC. Stepwise regression analysis revealed that catastrophising predicted total severity of clinical delusions and JTC predicted the cognitive dimension of clinical delusions. Both JTC and catastrophisation predicted the frequency and conviction associated with DLEs.
  
  
  CONCLUSIONS
  Both "Beckian" and psychosis-related cognitive biases may underlie delusions. Different aspects of clinical delusions and delusion-like experiences may be related to different cognitive biases.
authors.affiliation: II Department of Psychiatry, Medical University of Warsaw, 8, ul. Kondratowicza, 03-242 Warsaw, Poland. Electronic address: lgaweda@wum.edu.pl.
authors.forename: Ł
authors.initials: Ł
authors.lastname: Gawęda
authors.affiliation: Institute of Psychology, Jagiellonian University, Krakow, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Prochwicz
mesh_terms: D000223:Adaptation, Psychological; D000328:Adult; D001008:Anxiety Disorders / Q000150:complications; D003702:Delusions / Q000209:etiology / Q000523:psychology*; D003866:Depressive Disorder / Q000523:psychology; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D008603:Mental Health / Q000706:statistics & numerical data*; D008875:Middle Aged; D010555:Personality Inventory; D011618:Psychotic Disorders / Q000209:etiology / Q000523:psychology*; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000150:complications*; D012649:Self Concept; D011795:Surveys and Questionnaires
keywords: Cognitive biases; Delusion continuum; Delusions; Psychosis