how vital is the health insurance

Health care in the United States is provided by many separate legal entities. Health care facilities are largely owned and operated by the private sector. Health insurance plans are primarily provided by the private sector, with the exception of programs such as Medicare, Medicaid, the Children's Health Insurance Program and the Veterans Health Administration.
Uninsured Americans are less likely to have regular health care and use preventive services. They are more likely to delay seeking care, resulting in more medical crises, which are more expensive than ongoing treatment for such conditions as diabetes and high blood pressure. A 2007 study published in JAMA concluded that uninsured people were less likely than the insured to receive any medical care after an accidental injury or the onset of a new chronic condition. The uninsured with an injury were also twice as likely as those with insurance to have received none of the recommended follow-up care, and a similar pattern held for those with a new chronic condition.[119] Uninsured patients are twice as likely to visit hospital emergency rooms as those with insurance; burdening a system meant for true emergencies with less-urgent care needs.[120]