Evolution of Medicaid managed care systems and eligibility expansions.

The States of Tennessee, Hawaii, Rhode Island, Oklahoma, and Maryland initiated section 1115 demonstration projects to reform their State Medicaid programs, featuring large expansions of Medicaid managed care. These projects were controversial and chaotic in the beginning but have matured with time. Survey data indicate that Tennessee's expansion reduced uninsurance rates among low-income persons. States must periodically assess adequacy of capitation rates to ensure that enough plans participate. States and plans gradually developed their quality assurance systems but still need improvement.