According to CMS Internet Only Manual (IOM), Publication 100-08, Medicare Program Integrity Manual, Chapter 10, Section 10.6.13 - Ordering/Certifying Suppliers, depending upon state law, the following physicians and non-physician practitioners are permitted to order or certify items or services for Medicare beneficiaries:

• Doctors of medicine or osteopathy
• Doctors of dental surgery or dental medicine
• Doctors of podiatry
• Doctors of optometry
• Physician assistants
• Certified clinical nurse specialists
• Nurse practitioners
• Clinical psychologists
• Certified nurse midwives
• Clinical social workers
• Residents meeting eligibility criteria (Pursuant to CMS Final Rule CMS-6010-F, residents (as defined in 42 CFR § 413.75 and which includes interns and fellows) who are enrolled in an accredited graduate medical education program in a state that licenses or otherwise enables such individual to practice or order these items or services may enroll in Medicare to order and certify).