Although experts recommend regularly reassessing adolescents\u27 risk for violence, it is unclear whether reassessment improves predictions. Thus, in this prospective study, we tested three hypotheses as to why reassessment might improve predictions, namely the shelf-life, dynamic change, and familiarity hypotheses. Research assistants (RAs) rated youth on the Structured Assessment of Violence Risk in Youth (SAVRY) and the Youth Level of Service/Case Management Inventory (YLS/CMI) every three months over a one-year period, conducting 624 risk assessments with 156 youth on probation. We then examined charges for violence and any offence over a two-year follow-up period, and youths\u27 self-reports of reoffending. Contrary to the shelf-life hypothesis, predictions did not decline or expire over time. Instead, time-dependent area under the curve scores remained consistent across the follow-up period. Contrary to the dynamic change hypothesis, changes in youth\u27s risk total scores, compared to what is average for that youth, did not predict changes in reoffending. Finally, contrary to the familiarity hypothesis, reassessments were no more predictive than initial assessments, despite RAs\u27 increased familiarity with youth. Before drawing conclusions, researchers should evaluate the extent to which youth receiving the usual probation services show meaningful short-term changes in risk and if so, whether risk assessment tools are sensitive to these changes
