The Impact of Medicaid Managed Care on Primary Care Physician Participation in Medicaid
Medical Care, Vol. 43, No. 9, pp 911-920, September
Greene, J., Blustein, J. & Remler, D.
Research Design: We used 3 waves of a large, nationally representative sample of primary care physicians from the Community Tracking Study followed across time (1996-2001) to estimate the impact of changing Medicaid managed care penetration levels on physician participation in the program. County-level Medicaid managed care penetration rates were collected directly from state Medicaid agencies for the study.
Findings: In cross-sectional bivariate and multivariate analyses, Medicaid managed care penetration is significantly associated with physician participation in Medicaid; however, the relationship is nonmonotonic, of small magnitude and generally not in the anticipated direction. Our analyses indicate that a 10 percentage point increase in managed care penetration would reduce the likelihood that physicians participate in Medicaid on average by 2.9 percentage points. Although commercial MCO penetration exhibited a small positive, linear relationship with physician participation, this was not sufficient to offset the effects of Medicaid-dominant MCO penetration. Panel data analysis supported these findings.
Conclusions: This study failed to find that increases in Medicaid managed care lead to increased primary care physician participation in Medicaid during the period 1996-2001.