The MRO interview, evaluation of legitimate medical explanations, prescription review, documentation requirements, and verification decisions.
A laboratory reports a driver's specimen as substituted. During the verification interview, the driver provides a medical history that the Medical Review Officer (MRO) determines may present a reasonable basis for a legitimate medical explanation. The MRO directs the driver to undergo a further medical evaluation by a referral physician. Which of the following is a required action for the MRO?