French Validation of the Self-Screening Prodrome, an Early Detection Tool for Psychosis

Abstract

Introduction

Preventive actions for individuals with clinical high risk for psychosis (CHR) are highly effective in reducing the risk of transition to psychosis. Improving the identification of at-risk individuals could enable earlier access to care and reduce both the personal and societal burden of psychotic disorders. In this context, screening questionnaires are essential tools for identifying early signs of psychosis in the general population and referring individuals with a CHR to specialised centres. The Self-Screen Prodrome questionnaire (S-PRO) is a screening questionnaire designed for this purpose. The first aim of this study is to validate the French version of this instrument. Secondly, we will explore the reduction of its items to improve precision and reduce administration time.

Methods

Following international guidelines, items were translated and pre-tested for clarity and relevance. Seventy-two CHR patients or patients experiencing a first psychotic episode according to the Comprehensive Assessment of At-Risk Mental States (CAARMS) criteria were included.

Results

Cronbach's alpha score of the French version of the S-PRO was 0.893, and specificity/sensitivity were respectively 0.86 and 0.61 with an optimal cut-off point at 15 positive items. Using logistic regression, we reduced the S-PRO to a 12-items version. Cronbach's alpha score of the S-PRO12 was 0.71, and specificity/sensitivity remains the same, respectively 0.86 and 0.61.

Discussion

These results suggest that the 12-item version of the S-PRO could be an effective screening instrument for use by general health practitioners in primary care.