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.

Addressing the elephant in the screening room: an item response theory analysis of the Prodromal Questionnaire (PQ-16) for at-risk symptoms of psychosis.

OBJECTIVE: Within the context of patients at-risk of psychosis, where a variety of symptoms are present, identifying the most discriminative symptoms is essential for efficient detection and management. METHODS: This cross-sectional online study analyzed individuals from the general population in order to better assess their risk of presenting symptoms belonging to the clinical high risk (CHR) for psychosis, called "CHR-related symptoms". The Prodromal Questionnaire-16 (PQ-16) served as a self-report screening tool. Item response theory (IRT) with a graded response model was used to assess the discrimination and difficulty of its criteria. RESULTS: The analysis included 936 participants (mean age: 21.5 years; 28.1% male, 71.9% female). "Déjà vu" stood out for its high discriminative power, while "Voices or whispers" and "Seen things" demonstrated strong precision relatively to the other CHR-related symptoms. Conversely, "Smell or taste" and "Changing face" were associated with the most severe cases relatively to the other CHR-related symptoms. CONCLUSION: This study identified the most indicative CHR-related symptoms to emphasize their significance in accurately assessing severity and guiding targeted preventative interventions.