Final answer:
The question refers to medical billing and coding, where modifier 50 is used to denote bilateral procedures on a bill. The code for the procedure is listed once with the modifier to indicate that the service was performed on both sides of the body.
Step-by-step explanation:
The question pertains to medical billing and coding, specifically how to list procedural codes when a service has been performed bilaterally. In the healthcare industry, modifier 50 is often used to indicate that a procedure was performed on both sides of the body. For example, if a surgeon performs arthroscopy on both knees during the same operation, the CPT (Current Procedural Terminology) code for the arthroscopy would be listed once on the bill, followed by modifier 50. This indicates that the listed procedure should be considered as having been done twice, once on each side of the body.