Coinsurance - A provision in a member's coverage that limits the amount of coverage by the plan to a certain percentage, commonly 80%.  Any additional costs are paid by the member out of pocket.

Copayment (Co-Pay) - That portion of a claim or medical expense that a member must pay out of pocket.  Usually, a fixed amount such as $30.  

Deductible - That portion of a subscriber's (or member's) health care expenses that must be paid out of pocket before any insurance coverage applies, commonly $1,000-$2,000.  May also apply only to one portion of the plan coverage (ex. Radiology services).

Explanation of Benefits (EOB) - A statement mailed to a member or covered insured explaining how and why a claim was or was not paid.

Formulary - A listing of drugs that a physician may prescribe.

Gatekeeper - An informal term that refers to a Primary Care Physician.  All care must be authorized by the Primary Care Physician before rendered.

Health Maintenance Organization (HMO) - A licensed health plan (licensed as an HMO) that utilizes designated (usually Primary Care) physicians as gatekeepers. 

Member - An individual covered under a managed care health plan.  May be either the subscriber or a dependent.

Non Par - Short for nonparticipating.  Refers to a physician that does not have a contract with the health plan.

Preferred Provider Organization (PPO) - A plan that contracts with independent providers at a discount for services.

Pre-certification - The process of obtaining certification or authorization from the health plan for a visit to the specialist or for routine hospital admissions.

Primary Care Physician (PCP) - Generally applies to internists, pediatricians, family physicians and general practitioners.

Subscriber - The individual or member who has health plan coverage by virtue of being eligible on his other own behalf rather than as a dependent.