Abstract:
Previous empirical studies on the relationship between psychotic
symptoms and dissociative disorders focused on auditory
hallucinations only or employed limited statistical analyses. We
investigated whether the frequency of Schneiderian first rank
symptoms (FRS) predicts the presence or absence of
a dissociative disorder (DD). Psychiatric in-patients (n = 116)
completed measures of dissociation, FRS and general psychological
distress (GPD). DD diagnoses were confirmed by multidisciplinary
teams or administering the Structured Clinical
Interview for DSM-IV Dissociative Disorders-Revised (SCID-D-R).
The FRS were recorded in the Multidimensional Inventory of
Dissociation (MID) and a mean score obtained for 35 relevant
items: Voices arguing, voices commenting, made feelings, made
impulses, made actions, influences on body, thought withdrawal,
and thought insertion. A global severity index (GSI) of GPD
was obtained from the Symptom Checklist–90–Revised (SCL-90-
R). Logistic regression models examined whether FRS predict
diagnostic classification of patients under a DD (n = 16) or not
(n = 100), controlling for GSI. The overall fit of the model was
significant (p = .0002). DD was correctly classified using frequency
of FRS, controlling for GSI. The latter was moderately
associated with FRS (r = 0.56). FRS more than doubled the odds
of a DD diagnosis (odds = 2.089; 95% CI = 1.409–3.098; correct
classification rate 87.1%). The study provides convincing evidence
that FRS are closely related to DDs. FRS should alert
clinicians to consider DDs in differential diagnosis of psychiatric
in-patients. Future research should analyze whether FRS also
predict a diagnosis of schizophrenia or other psychiatric
disorders.
