How is "co-insurance" defined in health insurance?

Co-insurance is defined as the percentage of costs that are shared between the insured individual and the insurance provider after the deductible has been met. This means that once the insured has paid their deductible, they are responsible for a specific percentage of the remaining medical expenses, while the insurer covers the rest. For example, if a health insurance plan has a co-insurance clause of 20%, the insured would pay 20% of each claim, and the insurer would pay 80%. This arrangement helps to keep premiums lower and encourages insured individuals to be more mindful about their healthcare expenses, as they will have a direct financial incentive to consider the costs involved in their medical care.

In contrast, the other options refer to different concepts in health insurance. For instance, the amount paid before coverage starts describes a deductible, and a fixed amount paid per doctor visit relates to co-payments. The premium, typically paid annually or monthly, is simply the cost of maintaining the insurance policy itself and does not pertain to the sharing of costs post-deductible.