Primary care affiliations of adults in a methadone program with onsite care.

Methadone maintenance treatment programs (MMTP) often provide onsite primary care. It is unclear whether patients in these settings consider the MMTP their usual source of care. We conducted cross-sectional interviews of 62 adults in an inner-city MMTP with onsite primary care to determine their usual source of care. Program enrollment ranged from 1 to 27 years (median, 4) and 63% attended > or = 5 days per week. Seventy-six percent had > or = 1 chronic disease. Only 53% reported having a usual source of care, which included hospital-based clinics (45%), the MMTP (23%), private physicians (19%), other sites (13%). Patients were more likely to identify the MMTP as their usual source of care if they had cardiovascular disease (RR 6.9, 95% CI 2.2 to 21.9) or HIV (RR 5.6, 95% CI 1.7 to 18.5). Successfully promoting appropriate utilization of onsite primary care may require a better understanding of MMTP patients' perceptions of primary care.