Cross-Cultural Evaluation of Schneider’s First-Rank Symptoms of Schizophrenia: A Report from the International Pilot Study of Schizophrenia

The authors analyzed diagnostic data collected in nine countries in an effort to determine the clinical usefulness of Kurt Schneider's II "first-rank symptoms" (FRSs) of schizophrenia. The study specifically sought to determine whether the prevalence of FRSs in patients diagnosed as schizophrenic (N = 811) justified their use in diagnosis, what the frequency distribution was among FRSs, and whether or not FRSs were pathognomonic of schizophrenia, as Schneider claimed. The findings showed that FRSs do occur with sufficient frequency to have potential diagnostic usefulness and that each of the nine FRSs analyzed is highly discriminating for schizophrenia. However, since FRSs were also reported in patients receiving other psychiatric diagnoses. FRSs cannot be considered absolutely discriminating for schizophrenia.