Perkins DO, Loohuis LO, Barbee J, et al. - In persons who meet research criteria for a high-risk syndrome, the 2-year risk of psychosis is nearly 15%−25%; the development and implementation of preventive interventions may benefit from improvements in risk prediction accuracy. Researchers aimed at ascertaining polygenic risk score (PRS) prediction of subsequent psychosis in these persons and at evaluating the impact of adding the PRS to a previously validated psychosis risk calculator. They followed 764 persons meeting research criteria for psychosis high risk and 279 unaffected individuals for up to 2 years. The latest schizophrenia and bipolar genome-wide association studies were the bases of the PRS. Stressful life events, trauma, disordered thought content, verbal learning, information processing speed, and family history of psychosis were the variables in the psychosis risk calculator. The PRS led to discrimination of psychosis converters from nonconverters and a modest improvement in individualized psychosis risk prediction when added to a psychosis risk calculator. In persons at high risk for psychosis, promising value of the schizophrenia PRS in enhancing risk prediction was suggested, although poor performance limited its potential value in persons of non-European ancestry.