"Psychotic Disorders in the Diagnostic Stability of a Portuguese Ward - Diagnostic Retrospective Analysis"

Psychiatric diagnosis is based on clinical manifestations, resulting from patients' internal state, their life situation, the evolution of their condition and the response to our interventions. There are currently few objective data which help to establish the diagnosis which is why this is based on diagnostic criteria such as the Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM defines entities by their diagnostic stability, however there are several causes of variability as categorised by Spritzer et al. (1987): subjects variance (changing in patients), occasions variance (different episodes), information variance (new information) and observation variance (different interpretations). This paper aims to determine the diagnostic stability of patients with Psychotic Disorders among patients readmitted to our Psychiatric Unit.

Retrospective analysis of the diagnoses of patients with Psychotic Disorders who had been readmitted to our unit. We analysed data from the last 12 years - 5422 admission episodes with 507 patients with a relevant diagnosis in this period.

Psychiatric diagnosis does evolve over time, nevertheless some diagnostic groups show a relatively significant stability over time - Bipolar Disorder and Schizophrenia with 69% and 77% stability, respectively. Diagnosis such as Depressive Psychosis and Drug-induced psychosis show a significantly lower stability (8% and 21%, respectively).

Knowing our own reality can make us aware that a cross-sectional view of patients can be insufficient and only time can determine a clear diagnosis. This study may help us to understand how psychotic disorders evolve.