Validation du biais contre les indices infirmatoires chez un échantillon francophone de patients schizophrènes

Abstract

PurposeThe purpose of this study was to verify the generality of the bias against disconfirmatory evidence in a French-speaking sample of schizophrenic patients. This bias is a heightened persistence of incorrect interpretations in front of contradictions, previously demonstrated in schizophrenic patients coming from non-French-speaking communities. MethodIn a pictorial decision task, 20 schizophrenic, 20 depressive and 20 control participants reappraised during eight successive steps, six interpretations proposed for emotionally neutral but initially incomplete pictures. Each step added a fragment of the picture represented. The reappraisal of the plausibility of incorrect interpretations between each step (change score [CS]) was measured for all the participants. The positive and negative symptoms scale as well as the scale for the assessment of positive symptoms were only administered to schizophrenic patients. ResultsEvolution of CS as a function of the seven last steps was significantly less pronounced in the schizophrenic samples. Only the negative dimension of the PANSS was correlated to the CS. DiscussionThese results replicated the BADE in a small French-speaking schizophrenic sample. The absence of a significant correlation between the BADE and the positive symptoms and measures of delusion was discussed with regard to both the small size of the sample and the explicative status of this bias.