Medicare Part B covers procedures and services required for treatment or diagnosis of an illness or injury as well as preventative care, as of 2015. This includes flu shots, psychological services, physician fees, blood tests, participation in clinical trials, surgery, necessary medical equipment and ambulance transportation.
Determination of coverage for a specific service depends on federal and state requirements, as well as local companies that run Medicare programs. Part B benefits under a Medicare Advantage Plan, which combines Part A and Part B benefits, differ from Original Medicare, Part A or Part B, as the services available depend on the private insurance provider. Plans still meet federal coverage standards for medically necessary services. Many Medicare Advantage Plans also provide prescription coverage. Part B coverage requires a premium payment and deductible by the insured.
Coverage for hospital stays, nursing homes and home health services falls under Medicare Part A. Services include 90 days of inpatient hospital stays during each benefit period and inpatient psychological care. Medicare Part C contains private insurance plans using Medicare assignments. Medicare Part D provides private prescription coverage.
Medicare Part B does not cover homeopathic medical treatments, eye care, dental procedures not medically necessary, vaccines and over-the-counter medicine or at-home treatments.