Tex. Insurance Code § 1301.052

An insurer offering a preferred provider benefit plan may not refuse a request made by a physician participating as a preferred provider under the plan and an advanced practice nurse or physician assistant to have the advanced practice nurse or physician assistant included as a preferred provider under the plan if:

(1) the advanced practice nurse or physician assistant is authorized by the physician to provide care under Subchapter B, Chapter 157, Occupations Code; and

(2) the advanced practice nurse or physician assistant meets the quality of care standards previously established by the insurer for participation in the plan by advanced practice nurses and physician assistants.