42 CFR §424.3

As used in this part, unless the context indicates otherwise— HCPCS means Healthcare Common Procedure Coding System. ICD-9-CM means International Classification of Diseases, Ninth Revision, Clinical Modification. Nonparticipating hospital means a hospital that does not have in effect a provider agreement to participate in Medicare. Participating hospital means a hospital that has in effect a provider agreement to participate in Medicare.