 Some services, such as outpatient mental health care, are limited, and more costly forms of care, diagnosis, or treatment may not be covered.Experimental treatments and elective services that are not medically necessary (such as elective plastic surgery) are almost never covered.Other choices for managing care are case management, in which patients with catastrophic cases are identified, or disease management, in which patients with certain chronic diseases like diabetes, asthma, or some forms of cancer are identified.