What is the difference between a CPT code and an ICD-10-CM code?

• A. CPT codes describe diagnoses; ICD-10-CM codes describe procedures.
• B. CPT codes describe diagnoses; ICD-10-CM codes describe procedures.
• C. CPT codes describe payer requirements; ICD-10-CM codes describe patient demographics.
• D. CPT codes and ICD-10-CM codes are interchangeable.

Answer: (B)

In medical coding, CPT codes describe the procedures and professional services that were performed, such as a surgical procedure, an imaging study, or a clinic visit. ICD-10-CM codes describe the patient's diagnoses or the reason for the encounter, like a specific illness or condition that prompted the service. On a claim, CPT shows what was done, while ICD-10-CM explains why it was done and supports medical necessity. Note that for inpatient hospital procedures, the appropriate coding system is ICD-10-PCS, not CPT. These systems complement each other and are not interchangeable, each serving a distinct purpose in billing and documentation.