(a) A licensed audiologist may not sell a hearing instrument to a person under 18 years of age unless the person or the parent or guardian of the person presents to the audiologist a written statement signed by a licensed physician stating that:
(1) the person's hearing loss has been medically evaluated during the six-month period preceding the date the statement is presented; and
(2) the person may be considered a candidate for a hearing instrument.
(b) Whenever practicable, the medical evaluation described by Subsection (a)(1) should be performed by a licensed physician who specializes in diseases of the ear.