Designing and piloting a sequential multiple assignment randomized trial for opioid prevention among youth in the legal system.

Youth in the legal system are vulnerable to initiation and escalation of opioid use. The transition period during which a young person is released from the institutional setting to the community is a critical window of opportunity for preventive intervention targeting the uptake and intensification of opioid and other drug use. Adaptive preventive interventions are a promising approach to systematically varying the timing and intensity of substance use preventive interventions for these youth.