What are the two general kinds of intermediaries that do risk-pooling in the US healthcare system? Describe at least one important difference between them.

The two general kinds of intermediaries that do risk-pooling in the US healthcare system are insurance companies and government programs.

1. Insurance Companies: These are private entities that individuals or their employers pay premiums to in exchange for coverage of healthcare costs. They pool the risk among their insured individuals. The more people they insure, the more they can spread the risk and keep premiums lower. Insurance companies can be for-profit or non-profit entities. They often have contracts with specific healthcare providers and may only cover services provided by those entities.

2. Government Programs: These are publicly funded programs that provide healthcare coverage to specific populations. Examples include Medicare (for the elderly), Medicaid (for low-income individuals and families), and the Children's Health Insurance Program (CHIP). These programs are funded by taxpayers and are meant to ensure that vulnerable populations have access to healthcare. They often cover a broader range of services than private insurance, but may have more restrictions on who can receive coverage.

One important difference between these two types of intermediaries is their funding source. Insurance companies are funded by premiums paid by individuals or their employers, while government programs are funded by taxpayers. This difference in funding sources often leads to differences in who is covered, what services are covered, and how much individuals have to pay out-of-pocket for their care.