“Diagnostic or treatment center” means a facility for the diagnosis or diagnosis and treatment of ambulatory patients (1) that is operated in connection with a hospital, or (2) where patient care is under the professional supervision of persons licensed to practice medicine or surgery in the State, or, in the case of dental diagnosis or treatment, under the professional supervision of persons licensed to practice dentistry in the state.
Source:
Section 129420, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=HSC§ionNum=129420..