Decomposition of Economic Inequality in Needle and Syringe Programs Utilization to its Determinants among Men Who Inject Drugs in Tehran using Blinder-Oaxaca Decomposition Method.

The results showed that contribution of economic inequalities in utilization of NSPs was primarily explained by the differential effects of HIV risk perception and HIV knowledge among PWID. Reducing HIV risk perception and increasing HIV knowledge might be essential to efforts to eliminate inequalities in access to NSPs among PWID.