Impacts of risk thresholds and age on clinical high risk for psychosis: a comparative network analysis

One of the main goals for supporting people with a psychotic disorder is early detection and intervention, and the detection of Clinical High Risk (CHR) is a major challenge in this respect. This study sought to compare core symptoms of CHR for psychosis networks based on two CHR self-assessment tools, across different risk thresholds and age groups. This cross-sectional online investigation analyzed 936 individuals for CHR, in France and the UK, with the Prodromal Questionnaire-16 (PQ-16) and the Perceptual and Cognitive Aberrations (PCA). Twelve different symptom networks were constructed, assessing relationships, compactness, centrality, predictability, and comparisons between them, based on different thresholds and age groups. In the above-threshold PQ-16 network, the most central symptom was "Voices or whispers"; in the PCA network, the most central symptom was "Non-relevant thoughts distract or bother". They presented low overall predictability. No significant difference was found between them. This study makes three key contributions. First, this cross-network analyses highlight the relative importance of some central symptoms. Secondly, comparisons between networks demonstrate the unity of the CHR construct across scales, thresholds, and ages, affirming its phenotypic homogeneity, an essential issue for patient care pathways. Thirdly, the low average network predictability suggests the existence of unconsidered symptoms within these CHR networks. These results shed light on the organization of CHR symptoms using routine clinical questionnaires, offering insights for preventive targets in a logic of precision semiology.