[Pain patients show a higher hindsight bias]

Research on pain-related cognitions has up to now predominantly relied upon introspective questionnaire data. Experimental cognitive psychology offers an alternative way of access to the cognitive aspects of chronical pain. Building on the assumption that information-processing is in part uncontrolled, automatic and pre-attentive, similar processes are also expected to be relevant for pain-relevant cognitions and to be involved in health-related convictions and in coping strategies that can be assessed with questionnaires. Cognitive-psychological research has established the "hindsight bias" as a robust phenomenon that occurs uncontrolled and automatically in diverse contexts when a prior judgment or prediction is assimilated to information received later on. The hindsight bias may be regarded as a manifestation of a universal cognitive mechanism, meaning that information (including information about emotional states) available at a given time will change the memory of prior judgments or of predictions of future events and results of behavior. Cognitive biases similar to the hindsight effect have been demonstrated in chronical pain patients. The present work elaborates the hypothesis that pain patients differ from other groups in the size of the hindsight bias and in its composition and outlines how it can contribute to the chronification of pain. Data from a hindsight-bias experiment comparing pain patients, psychiatric patients and students are analyzed using alternatively a traditional global hindsight bias score ("Hell-Index") and a multinomial modelling approach. The hindsight-effect was observed in the usual extent in the student control group, but was significantly greater in the pain group and absent in the psychiatric sample. In addition to this global finding, multinomial modelling revealed group differences in specific model parameters. This method of analysis thus proved as promising for the assessment of cognitive aspects of clinical disorders.