P-1013 - Psychopathological assessment of the ultra-high risk state of psychosis: a five factor solution

The ultra-high risk state of developing a psychosis is mainly characterized by attenuated or transient full-blown psychotic symptoms. It can be assessed with the structured interview for prodromal symptoms (SIPS), comprising four domains: positive, negative, disorganization and general symptoms. As the scores of the SOPS sub-domains are regularly used to perform domain-related analyses the stability of the suggested domain structure and item composition is of major interest. Method: SIPS (version 3.0) data from n=243 participants of the European Prediction of Psychosis Study (EPOS) were used for the current analysis. Inclusion criteria comprised ultra-high risk criteria and the basic symptom criterion COGDIS. The EPOS investigators received extensive training by one of the scale''s authors (Tandy J. Miller, PhD). Pairwise interrater concordance for SIPS was 77%, which was determined acceptable by the training team. A principal component analysis was performed (Eigenvalues > 1, varimax rotation). Results: A five factor solution emerged. Factor 1 was primarily defined by a loss of intentionality, functioning and stress tolerance, factor 2 by anhedonia and affective blunting, factor 3 by cognitive and behavioural disorganization, factor 4 by delusions. Sleep disturbances and perceptual abnormalities/hallucinations have both been associated with dopaminergic disturbances, this may explain their common appearance on factor 5. Discussion: The originally suggested structure of the SIPS proofed not to be stable and was replaced by a five-factor solution. Our results suggest considering a different item and factor structure in future SIPS based data analyses. [Copyright &y& Elsevier]