Health Care Fragmentation in Medicaid Managed Care vs. Fee for Service

Managed care plans often attempt to control health care costs through strategies designed to decrease health care utilization. However, the extent to which the resulting patterns of utilization represent high-quality care (compared to fee-for-service products) remains controversial. The authors sought to compare patterns of ambulatory care (including how diffuse or fragmented the care patterns were) for Medicaid fee-for-service beneficiaries vs. Medicaid managed care beneficiaries. A serial cross-sectional study of adults (>= 18 years old) was conducted using statewide Medicaid claims from New York State for calendar years 2010-2013. Beneficiaries were required to be continuously enrolled and have >= 4 ambulatory visits for each year they contributed data, yielding a sample of more than 1 million beneficiaries per year. Beneficiaries were characterized by age, sex, and case mix. For each year, ambulatory care patterns were compared across subgroups of beneficiaries using Poisson models (for numbers of visits and providers) and bounded Tobit models (for fragmentation scores). In 2010, among those who were not dual eligible, managed care beneficiaries had on average fewer visits (10.9 visits vs. 11.4 visits [P < 0.0001]) but more providers (3.8 providers vs. 3.3 providers [P < 0.0001]) and therefore more fragmentation (0.58 vs. 0.51 [P < 0.0001]) than fee-for-service beneficiaries, adjusting for age, sex, and case mix. These patterns persisted throughout the follow-up period and in sensitivity analyses. Less utilization is not necessarily more efficient care; a smaller number of visits spread across a larger number of providers creates more challenges for care coordination.