Schizophrenia spectrum disorders (SSD): an internet-based vignette study of real-world diagnostic accuracy and reliability among psychiatrists and clinical psychologists

Diagnosing psychiatric conditions in real-life scenarios is challenging, as patients' presentations often differ from the simplified descriptors in mainstream taxonomies. This study aimed to assess the accuracy and reliability of ordinary psychiatrists and clinical psychologists in diagnosing schizophrenia spectrum disorders (SSD) through vignettes extrapolated from real-world clinical presentations. We assessed the diagnostic performance of 70 international clinicians (psychiatrists and clinical psychologists) using an online survey. Besides the socio-demographic and professional backgrounds of the participants, the study presented two concise clinical vignettes, that portray different manifestations of typical SSD cases. Participants were asked to evaluate these vignettes, with the primary focus on identifying the most plausible diagnostic hypothesis. In the first vignette, 71.4 % (50/70) identified an SSD as the main diagnosis, whereas about 23.2 % (14/60) made the same choice for the second vignette. Eleven clinicians (18.3 %) correctly identified both vignettes as SSD cases. The inter-rater diagnostic agreement was fair and significant (Fleiss’ Kappa = .29, p < .00). The findings indicate poor diagnostic accuracy and reliability for SSD among ordinary psychiatrists and clinical psychologists. When compared to leading international psychiatrists (LIPs) the results suggest a concerning gap in diagnostic proficiency, particularly in real-world clinical scenarios. The low rates of correct diagnosis and fair inter-rater agreement raise concerns about the gradual erosion of in-depth psychopathological understanding in clinical practice. Improving diagnostic accuracy through better training could have profound implications for patient care and treatment outcomes in mental health settings. • Diagnostic proficiency in the domain of the schizophrenia spectrum disorders is rather poor. • Inter-rater reliability in diagnosing SSD was fair and statistically significant. • The performance of ordinary clinicians was lower than that of top psychiatrists.