BACKGROUNDS: A diagnostic simulation exercise was carried out using John Nash's case (the 1994 Mathematics Nobel Prize winner and described as suffering from schizophrenia) to introduce the Operational Criteria Checklist for Psychotic Illness (OPCRIT) and discuss the uncertain boundaries between some of the diagnostic categories presented by the instrument, as well as the use of dimensional diagnosis in psychiatry. METHODS: Data were obtained from John Nash's biography (written by Sylvia Nasar) and from the movie A Beautiful Mind. The authors discussed the symptoms shown in both the biography and the movie and then entered data into the OPCRIT program. Because consensus was not reached in some items, two additional simulations were carried out. In these, three items were modified, in order to investigate the effects of these changes on diagnosis: thoughts racing (31st item), increased sociability (53rd item), and relationship psychotic/affective symptoms (52nd item). RESULTS: The diagnoses provided by two of the simulations were schizophrenia (DSM-IV) and undifferentiated schizophrenia (ICD-10). Other results included schizoaffective disorder/bipolar type (DSM-IV) and schizoaffective disorder/manic type (ICD-10). It is important to emphasize that the 52nd item (relationship psychotic/affective symptoms) was the only one with an effect on diagnosis when altered (schizophrenia vs. schizoaffective disorder). DISCUSSION: The boundaries between schizophrenia and schizoaffective disorder are not clear and explain the frequent difficulty faced by psychiatrists in establishing diagnosis. CONCLUSIONS: This exercise revealed the importance of a detailed assessment of the course of illness for a correct diagnosis, emphasizing the relationship between psychotic and affective symptoms. We emphasize the importance of dimensional diagnosis and the need for further studies in order to validate the diagnostic categories currently used.
Diagnosis; schizophrenia; OPCRIT; schizoaffective disorder
