Summary

Young adults struggling with antisocial behavior and addiction continue to face persistent challenges despite ongoing intervention efforts. Research highlights the importance of examining daily fluctuations in maladaptive behaviors using the Experience Sampling Method (ESM), which captures mood and behavior variations in real-world settings, unlike traditional laboratory studies with limited ecological validity. Building on our pilot findings, this study employs a validated ESM approach to investigate momentary changes in aggression (proactive, reactive) and substance use (alcohol, cannabis, and other drugs) among young adults with prior legal involvement.

Approximately 50 young adults receiving social welfare support in Rotterdam, Netherlands, will complete brief (2–3 minute) surveys three times a day, seven days a week, for 4 weeks. These surveys will assess fluctuations in key state variables, with a focus on aggression (proactive, reactive, provoked) and substance use (craving, consumption) over the past hour. The study aims to determine whether aggression and substance use fluctuate within this sample and to examine their associations, such as whether they co-occur or predict one another.

Additionally, we will explore whether other state variables influence daily fluctuations in these behaviors. These variables can be categorized into “need” states, which reflect heightened risk factors such as negative mood, high stress, fatigue, high-risk locations, craving, and provocation. However, they can also be categorized into “opportunity” states, which represent protective or mitigating factors such as openness to information, positive mood, social support, low stress, and low-risk locations. By distinguishing between these states, we aim to identify critical risk periods and contextual factors that precede maladaptive behaviors. These insights can inform future interventions, helping to develop more effective strategies to support antisocial young adults.