Definition of percentage participation

( coinsurance) plan where a portion of medical expenses are paid by an insured. Some health insurance policies provide that the insured shares expenses with the insurer according to a predetermined ratio. For example, many group health plans provide that, after paying a deductible amount, the insured pays a portion (usually 20-25%) of covered medical expenses. For some types of services, such as psychiatry or dentistry, the percentage participation, which the insured pays, may go as high as 50% of covered services.