Type of managed care organization. After any applicable deductible or copayment, all of an enrollee’s or member’s medical care costs are paid for in return for a monthly premium. However, due to the lock-in provision, all of the enrollee’s or member’s services (except for out-of-area emergency services) must be arranged for by the risk-HMO. Should the Medicare enrollee or member choose to obtain service not arranged for by the plan, he or she will be liable for the costs. Neither the HMO nor the Medicare program will pay for services from providers who are not part of the HMO’s health care system or network.

Health plan, health insurer, or self-funded employer that takes on financial responsibility for a provision that lists specific benefits and accepts prepayment for the cost of the medical care.