Deciding to risk it: toward a multivariate model of unsafe injecting behavior.

This paper reports on a set of studies which sought to explain why Australian injecting drug users (IDUs) continue to share injecting equipment despite the provision of needles and syringes, drug treatment, education programs, and HIV testing. A range of situational and psychological factors were implicated in risk-taking, and these are integrated into a theoretical model which reflects the decision-making processes that occur when IDUs decide to take a risk.