Which coding system is used for diagnoses in CBCS outpatient billing?

• A. ICD-10-CM
• B. CPT
• C. HCPCS Level II
• D. ICD-10-PCS

Answer: (A)

Diagnoses in outpatient billing are reported using ICD-10-CM, which is the coding system developed for documenting patient conditions and reasons for visits. In a CBCS claim, the ICD-10-CM diagnosis codes accompany the CPT or HCPCS procedure codes that describe the services performed. ICD-10-PCS is used for inpatient procedures, CPT handles procedures and services, and HCPCS Level II covers supplies and some non-physician services. So ICD-10-CM is the correct choice because it specifically codes the diagnoses for outpatient encounters. For example, a visit for diabetes would use an ICD-10-CM diagnosis code for diabetes, while the actual visit or procedure would be coded with CPT.