Health Maintenance Organization (HMO) : A health care plan that delivers comprehensive, coordinated medical services to enrolled members on a prepaid basis. There are three basic types of HMOs:

• Group/Staff HMO: Delivers services at one or more locations through a group of physicians that contracts with the HMO to provide care or through its own physicians who are employees of the HMO.

• An Individual Practice Association (IPA): Makes contractual arrangements with doctors in the community, who treat HMO members out of their own offices.

• Network HMO: Contracts with two or more group practices to provide health services.

In 1997, Field Representative's Manual provided the following definition, which was read to respondents if necessary.

"Health Maintenance Organizations, or HMOs, and Individual Practice Associations, or IPAs, are plans whose members are required to use only those doctors who work for or in association with the plan. Sometimes members may choose to go to doctors not associated with the plan, but usually at greater cost to the member. Generally, members do not have to submit claims for costs of medical care services."

The 2002 Manual provided the following terms:

Fee-For-Service: These are the "traditional kind of health care policy. Insurance companies pay fees for the services provided to the insured people covered by the policy. This type of health insurance offers the most choices of doctors and hospitals. You can choose any doctor you wish and change doctors at any time. You can go to any hospital in any part of the country. With fee-for-service, the insurer only pays part of your doctor and hospital bills. A fee-for-service plan pays for covered services after the services have been received. This is also known as an indemnity plan."

IPA: "a type of HMO that contracts directly with physicians in independent practices; and/or contracts with one or more associations of physicians in independent practices or multi-specialties. The plan is predominately organized around solo/single practices."

PPOs or Preferred Provider Organizations : "a form of managed
care, although not a "traditional" HMO. Enrollees in PPOs are encouraged to use designated, or preferred health providers. Financial incentives for individuals include lower payments or coinsurance, and maximum limits on out-of-pocket costs for in- network use. PPOs are less restrictive than HMOs in that visits to specialists are not dependent upon authorization by a member's primary care physician. Unlike HMOs, out of network usage is allowed by PPOs, although at a higher cost to the enrollee."

POS, or Point of Service Plans: "a form of managed care, although not a "traditional" HMO. POS plans allow for "opt-out", or out-of-network coverage, but accompanied by strong economic incentives to the enrollees to use network providers. POS plans usually use gatekeepers for referrals to specialists within the network. It is this attitude that most readily distinguishes a POS plan from a PPO."

Single Service Plan (SSP) : "a health insurance coverage paid for by the individual that provides for only one type of service. Examples of SSPs are dental care, vision care, prescriptions, nursing home care, hospice care, accidents, catastrophic care, cancer treatment, AIDS care, and/or hospitalization."

Thus, information about the type of insurance the person is also provided in: HINAME2 through HINAME4. Likewise, the complementary variables HI1PCOV through HI4PCOVindicate coverage status for the individual under each plan.

Persons with three or more plans have a "yes" response to the HIPRIVGT2 variable (available for 2004 forward). Additional information for the third and fourth plans for a person is available through a Data Research Center.