Final answer:
A medical assistant should note the details of a missed appointment in the patient's medical record, including attempts to contact the patient and any rescheduling information.
Step-by-step explanation:
When a patient fails to keep an appointment, the medical assistant should make a detailed note on the patient’s medical record. This note should include the date and time of the missed appointment, any attempts to contact the patient, the patient’s response if any, and whether the appointment was rescheduled. Keeping accurate and detailed records of missed appointments is crucial for managing patient care effectively and for legal documentation. It helps the healthcare provider to monitor patients' compliance with treatment plans and to identify any patterns of noncompliance that may need to be addressed.