Additional outcomes include self-reported and biochemically confirmed seven-day abstinence at six months , self-reported seven-day , thirty-day , and continuous abstinence at twelve months , intervention dose response at six and twelve months for AR+IVR recipients , incremental cost-effectiveness of AR+IVR intervention compared to usual care at six and twelve months , and health-care utilization and expenditures at twelve months for AR+IVR recipients compared to UC .
