ImportanceÌý Psychiatry has struggled to clarify the types of mental turmoil that are associated with mass violence. While the problem is complex, it may present an opportunity to improve research, as well as inform public dialogue about what types of mental illness are actually associated with such mass tragedies.

ObservationsÌý Assuring the diagnostic accuracy of those who commit mass violence is challenging due to the retrospective nature of the analysis and lack of reliable psychiatric data. Psychiatric research has begun to use a dimensional approach that may be well suited to the study of mental illness in perpetrators of mass violence. This approach aggregates psychiatric symptoms into 3 domains of psychopathology: (1) internalizing, (2) externalizing, and (3) psychotic experience. This approach has practical clinical use and research support. A dimensional approach may help clear up misconceptions about the rate of psychosis in mass violence perpetrators, as well as reveal the most common dimensions of mental functioning associated with perpetrators.

Conclusions and RelevanceÌý Improved research methods are needed to clarify and prevent mass violence. More precisely identifying the symptoms and mental turmoil of perpetrators may be associated with improved early identification and prevention. Because adolescence is a critical and formative period in which internalizing and externalizing problems arise, early interventions may have the best chance of reducing future mass violence.