French Validation of Schizophrenia Proneness Instrument- Child Youth

The clinical concept of a at risk mental state of developing psychosis is based on the identification of attenuated psychotic symptoms during the prodromal phase of psychoses (Schmidt et al., 2015). Early detection and support of these symptoms can delay the risk of transition to a first psychotic episode (van der Gaag, van den Berg, \& Ising, 2019).

The Basic Symptom approach enables detection at the earliest stage of the prodromal phase. It postulates that subtle, subjective manifestations predating attenuated psychotic symptoms are present very early in the prodromal phase of psychosis and also have predictive value for the risk of developing psychosis (F. Schultze-Lutter, 2009). Basic symptoms are assessed using the Schizophrenia Proneness Instrument, available in an adult (SPI-A) and child/adolescent (SPI-CY) version. These scales are part of the international recommendations for the assessment of patients with a Clinical State at High Risk of Psychosis (CHR-P) (Schmidt et al., 2015; F Schultze-Lutter et al., 2015). The SPI-A is validated in French under the name "Outil d'Evaluation du Risque Schizophrénique version adulte (OERS-A)" (Schultze-Lutter et al., 2007. French translation by JR. Teyssier with the collaboration of F. Gamma and P. Loulergue), but no French version of the SPI-CY has yet been validated.

In collaboration with Dr. Frauke Schultze-Lutter, the investigators have recently published a French translation of the SPI-CY (Schizophrenia Predisposition Instrument - Version for Children and Adolescents, F. Schultze-Lutter, M. Marshall, E. Koch, 2021. French translation by F. Bernardin and C. Dondé). This French translation must now be validated to ensure the inter-rater fidelity of the interview.

We therefore propose to study the inter-rater reliability of the French version of the SPI-CY by comparing ratings between clinicians who have undergone training in basic symptoms and in administering the SPI-A and SPI-CY tools by Dr. Schultze-Lutter. This validation will be carried out by comparing, on the one hand, the rating of the SPI-CY by a clinician A who has administered it to the patient and, on the other hand, the blind rating of a clinician B on the basis of the interview recorded by clinician A with his patient.

The investigators will also explore the links between the SPI-CY and other clinical scales such as the Multisensory Hallucination SCale (MHASC) (Demeulemeester et al., 2015), the Prodromal Questionnaire 16 (PQ-16) (Lejuste et al., 2021), the Audiograph (Giersch, Huard, Park, \& Rosen, 2021) and the Perceptual and Cognitive Aberrations (PCA) (McDonald et al., 2019).