Marcus has been addicted to online sports betting for three years. He has finally acknowledged his problem and wants to stop, but is unsure which path to take. His doctor discusses two options: cognitive behavioural therapy (CBT) or joining a self-management group (such as Gamblers Anonymous). The doctor also notes that Marcus's progress will depend on his readiness to change.

Discuss how both cognitive behavioural therapy (CBT) and self-management interventions could be used to reduce Marcus’s addictive behaviour. Refer to Marcus’s situation and Prochaska's six-stage model of behaviour change in your answer.