Integrative system dynamics: analysis of policy options for tobacco control in New Zealand

Tobacco use is a global problem and the health consequences are far reaching. Systemic approaches are needed to help investigate policies to reduce the adverse health effects of tobacco use. This paper provides an overview of the system dynamics model that has been developed to assist the Ministry of Health to evaluate the dynamic consequences of tobacco control policies in New Zealand. The model consists of six sectors: population; smoking prevalences; tobacco consumption; second hand smoke; relative risks and tobacco attributable deaths. The model is simulated for 20-30 years into the future. The simulation package used is 'iThink', and a user interface is presented for policy analysis. A range of illustrative scenarios are provided, including: business as usual; fiscal strategies involving less affordable cigarettes; harm minimization strategies involving either less addictive cigarettes or less toxic cigarettes and combinations of the above policies. The main output variables (performance measures) include current smoking prevalence, tobacco consumption and tobacco attributable mortality. Finally some areas for future model enhancement are identified.