Health insurance is a type of insurance whereby the insurer pays the medical costs of the insured if the insured becomes sick due to covered causes, or due to accidents. The insurer may be a private organization or a government agency. Market-based health care systems such as that in the United States rely primarily on private health insurance.

History and evolution

The concept of health insurance was proposed in 1694 by Hugh the Elder Chamberlen from the Peter Chamberlen family. In the late 19th century, early health insurance was actually disability insurance, in the sense that it covered only the cost of emergency care for injuries that could lead to a disability. This payment model continued until the start of the 20th century in some jurisdictions (like California), where all laws regulating health insurance actually referred to disability insurance.^[1] Patients were expected to pay all other health care costs out of their own pockets, under what is known as the fee-for-service business model. During the middle to late 20th century, traditional disability insurance evolved into modern health insurance programs. Today, most comprehensive private health insurance programs cover the cost of routine, preventive, and emergency health care procedures, and also most prescription drugs, but this was not always the case.

Private health insurance

A health insurance policy is a legal, binding contract between the insurance company and the customer. The largest difference between private sector health insurance and life insurance is that for life insurance, a person may purchase guaranteed renewable insurance for the whole of the insured's life at a constant premium rate, while health insurance is generally purchased year by year with generally no assurance of renewability and if renewable no guarantee that premium rates will not increase.

Before buying health insurance, a person typically fills out a comprehensive medical history form that asks whether the person smokes, how much the person weighs, and has the person ever been treated for any of a long list of diseases. Applicants can get discounts if they do not smoke and live a healthy lifestyle, which might encourage some people to quit smoking or make other improvements in their lifestyle. The medical history is also used to screen out persons with pre-existing medical conditions.

The following is a hypothetical example of a situation that might confront an insurance company: Suppose that a large number of customers of a particular insurance company contracted a rare disease and the hospital charged 10 million dollars a patient to treat them. The insurance company would then be faced with a choice of paying all claims without complaint (thus losing money and possibly going out of business) or denying the claims (thus outraging patients and their families, discouraging potential customers, and becoming a target for lawsuits and legislation).

Health insurance companies use the term "adverse selection" to describe the tendency for sick people to be more likely to sign up for health insurance.

Ex-post moral hazard is in essence the consequence of reduced prices for medical care. Since most insurance plans, whether public or private, reduce the out-of pocket cost of medical care, the behavior of individuals will be affected by those reduced prices. In the..