Mass. Gen. Laws ch. 176R § 2
The commissioner and the group insurance commission shall require that all carriers recognize nurse practitioners as participating providers subject to section 3 and shall include coverage on a nondiscriminatory basis to their insureds for care provided by nurse practitioners for the purposes of health maintenance, diagnosis and treatment. Such coverage shall include benefits for primary care, intermediate care and inpatient care, including care provided in a hospital, clinic, professional office, home care setting, long-term care setting, mental health or substance abuse program, or any other setting when rendered by a nurse practitioner who is a participating provider and is practicing within the scope of his professional license to the extent that such policy or contract currently provides benefits for identical services rendered by a provider of health care licensed by the commonwealth.
Mass. Gen. Laws ch. 176R, § 2