Rule 400 is a collection of regulations developed by the Colorado Medical
Board, with input from the public, that assist the courts in interpreting the law,
or statute, contained in the Medical Practice Act.
Specific examples:
  • Defines the responsibilities and level of PA supervision by the primary (versus secondary) supervising physician.
  • Includes requirements for performance assessments.
  • Outlines prescribing provisions.


The Medical Practice Act constitutes the law governing PA practice in Colorado. Changes to the Medical Practice Act only occur through the legislative process.
For example, a bill is created, sponsored by CO representatives, reviewed in the appropriate committee, and passed by each of the congressional houses.
Specific examples:
  • Only physicians can delegate the authority for PAs to practice medicine.
  • Physicians may supervise up to four PAs.
  • One PA will serve on the Colorado Medical Board.
  • PAs may own a medical practice, but physician shareholders must maintain a majority stake.

IMPORTANT: Sunset refers to a clause within the law that automatically
terminates a program, agency, or set of laws on a certain date.
Sunset of the Medical Practice Act occurs every 10 years and can be
described as a tool to ensure that the laws related to PA practice are
reviewed. If no action is taken, the laws pertaining to PA practice will
effectively expire. 2019 represents the scheduled sunset review of
the Medical Practice Act and is an opportunity for PAs to ensure that
the statute language is reflective of how PAs can provide patient care
within the highest level of their scope, ideally based on their education,
experience, and practice setting guidelines. CAPA intends to introduce
a member-driven legislative bill that advocates for PA practice
improvements. Also, Optimal Team Practice (OTP) is a policy that
was adopted by the AAPA in May 2017, though it is up to Colorado to
determine which, if any, changes should be considered. CAPA will be
working with Colorado PAs and physician stakeholder groups to explore
how policy points would impact PAs and patients alike. It is anticipated
that CAPA will produce a position statement in late 2018.