Final answer:
The term ''first-listed diagnosis'' is used instead of ''principal diagnosis'' in the outpatient setting.
Step-by-step explanation:
In the outpatient setting, the term ''first-listed diagnosis'' is used instead of ''principal diagnosis.''
The first-listed diagnosis refers to the primary reason for a patient’s visit to an outpatient facility. It is the diagnosis that is most responsible for the patient seeking care and is reported as the main reason for the encounter.
This term is used in outpatient coding and billing to ensure accurate reimbursement and proper documentation of the patient's condition.