Some are employed by the HMO while others are compensated in other ways, such as a capitated rate per person. In an IPA model, physicians are organized like an HMO, but practice in their own offices. A PPO falls between an HMO and a traditional indemnity plan. Patients choose from a network of physicians and facilities who have agreed to discount the cost of services, but are paid for each service rendered. Different providers may be selected at any time and the patient is not required to select a primary care provider.
Payment is based on a set fee schedule.
Physicians are not permitted to charge patients more than the agreed-upon fees. A POS plan is one that includes some type of managed care option, but allows participants to go outside of the managed care network by paying more. The first POS plans typically included a HMO, a PPO and an indemnity plan option. Now most POS plans are simply HMO plans with an opt-out feature. POS plans are often referred to as open-ended HMOs.