Stages of Change: Health Behavior Simulator

This simulator turns Prochaska and DiClemente's Transtheoretical Model of behavior change into a live population dynamics system. A cohort of 180 people, each rendered as an instanced 3D sphere on one of five concentric orbit rings, moves through Precontemplation, Contemplation, Preparation, Action and Maintenance as their individual self-efficacy and perceived decisional balance evolve over time. Turn up intervention strength to see decisional balance and self-efficacy growth accelerate forward progress; turn up relapse risk to watch agents with low self-efficacy spiral back from Action or Maintenance into Contemplation, exactly as the model predicts real behavior change is rarely a straight line.