The Frankfurt Complaint Questionnaire (FCQ) is a widely used method to investigate non-psychotic subjective experiences of schizophrenics. Less is known about its dimensional structure. Therefore, principal components analyses (PCA) were conducted with the FCQ data of 505 schizophrenics and 187 alcoholics. Furthermore, results of a former analysis using item-to-item comparisons between schizophrenics and alcoholics were examined. PCA yielded two factors called ‘dysphoric concomitants of severe illness particularly impairing concentration’ and ‘subjective experiences of perceptual uncertainties’. Neither of the factors was specific to schizophrenia. The item comparisons suggest that only a group of eight FCQ items (subscale ‘FCQ-S’) is specific to schizophrenia while ten items (‘FCQ-A’) are related more to alcoholism. The validity of FCQ-S and FCQ-A was confirmed: schizophrenics reached high scores in FCQ-S and low scores in FCQ-A; alcoholics scored high in FCQ-A and low in FCQ-S; schizophrenics with an additional alcohol disorder scored high in both of the subscales. It is concluded that direct group comparisons seem to be promising for the identification of non-psychotic subjective phenomena which are characteristic for schizophrenia.

Psychological and physical signs traditionally considered as indicators of conversion disorder had never been confirmed through empirical data. Nineteen of these signs were sought in 40 patients with proved neurological disorder and in 15 patients with conversion disorder. All neurological patients but one showed at least one of these signs and most presented several signs. All the signs but one were as frequent in neurological patients as in patients with conversion disorder. These signs are lacking specificity. Even when several signs are present, this finding has no diagnostic specificity.