A health maintenance organization shall establish and maintain a grievance procedure, approved by the commissioner, to provide reasonable and effective resolution of complaints initiated by enrolled participants concerning any matter relating to the interpretation of any provision of such enrolled participants' health maintenance contracts, including, but not limited to, claims regarding the scope of coverage for health care services; denials, cancellations, or nonrenewals of enrolled participants' coverage; and the quality of the health care services rendered, and which may include procedures for arbitration.
RCW 48.46.100