Tracking Oregon Medicaid patients' enrollment and health utilization patterns.

The Oregon Medicaid program consists of various sub-programs with different eligibility requirements and multiple health care delivery systems. Administrative events, such as the loss of Medicaid eligibility or a change in health plan enrollment, can cause disruptions in the continuity of medical care and may contribute to missed opportunities to provide appropriate medical services, including preventive care. Thus, in order to improve public health surveillance and describe the health care utilization patterns of Oregon's Medicaid beneficiaries, a standardized approach was developed to track the enrollment status of Medicaid patients for extended periods of time.