pre-existing condition

A physical or mental condition of an individual which is known to the individual before an insurance policy is issued. Before the Affordable Care Act (ACA), insurers could choose not to cover treatment for such a condition, at least for a period, raise rates because...

precision medicine

An emerging approach to disease treatment and prevention that takes into account individual variability in genes, environment, and lifestyle for each person.

preferred provider organization

A health care delivery system through which a number of providers contract to serve health plan enrollees on a fee-for-service basis at discounted fees. Providers agree to PPO discounts in the hope of gaining more patients. Patients may use any provider without a...


The cost of health plan coverage, not including any required deductibles or copayments. The cost of the premium may be shared between employers or government purchasers and individuals.

premium assistance

The use of funds available through public health coverage programs, especially Medicaid and CHIP, to purchase or help purchase private insurance or to pay Medicare premiums.