• First-rank symptoms of schizophrenia, such as thought insertion, thought broadcasting, "made" volition, and delusional perception, were introduced for purposes of diagnosis into a German university clinic. Such "Schneiderian" criteria were evaluated in 210 case records. Ratings employed formal definitions. Of 210 records examined, 69 (33%) of the schizophrenic patients had first-rank symptoms. The frequency of finding such symptoms in a group of schizophrenics is compared to other reports. There are considerable differences in frequency of individual symptoms as well as total number of such symptoms across centers, but the use of precisely agreed on definitions of first-rank symptoms may lead to better agreement.
Koehler K, Guth W, Grimm G. First-Rank Symptoms of Schizophrenia in Schneider-Oriented German Centers. Arch Gen Psychiatry. 1977;34(7):810-813. doi:10.1001/archpsyc.1977.01770190072007