The department shall accept the signature of a physician assistant on any certificate, card, form, or other documentation required by the department that the physician assistant's supervising physician or physicians may sign, provided that it is within the physician assistant's scope of practice, and is consistent with the terms of the physician assistant's practice agreement as required by chapter
18.71A RCW. Consistent with the terms of this section, the authority of a physician assistant to sign such certificates, cards, forms, or other documentation includes, but is not limited to, the execution of the certificate required in RCW
51.28.020. A physician assistant may not rate a worker's permanent partial disability under RCW
51.32.055.