Abstract for: Feedback Dynamics of Transport Disadvantage and Sustainable Modal Shift: A Systems Thinking Approach Using the Mobility Equity Transition Framework

Transport disadvantage(TD) and limited modal shift(MS) capacity remain critical barriers to equitable and sustainable mobility, especially in outer-metropolitan and regional areas. Their dynamic, mutually reinforcing relationship shaped by structural limitations and behavioural responses creates feedback loops that entrench car dependency. Conventional linear planning approaches overlook these non-linear interdependencies, leading to sub-optimal travel demand management and policy outcomes. This study applies a systems thinking approach using system dynamics and Causal Loop Diagrams (CLDs) to capture the complex, non-linear interactions between TD and MS. Structured by the COM-B framework, it categorises capabilities, opportunities, and motivations, drawing on literature and expert insights to reveal feedback mechanisms and behavioural patterns influencing sustainable travel outcomes. The study identified 703 causal relationships from literature and expert input, synthesised into COM-B-based CLDs. The opportunity domain showed highest complexity, highlighting structural influences. Integrated CLDs revealed six reinforcing and four balancing loops shaping mobility outcomes. The Mobility Equity Transition Framework defines four system states, explaining how feedback dynamics drive or constrain equitable modal shift and guide targeted policy interventions. The study shows that TD and sustainable MS are shaped by interacting capabilities, opportunities, and motivations, with the opportunity domain playing a central structural role. It highlights that single-domain interventions are insufficient. The systems thinking approach and Mobility-Equity Transition Framework reveal feedback dynamics, enabling policymakers to identify leverage points and design targeted strategies for equitable, long-term mobility transitions.