1. Inpatient and Outpatient Coding
The similarities and differences

2. Basic differences
Inpatient coders use the 10-PCS for procedure coding.
Outpatient coders use CPT and HCPCS Level II for procedure and service coding. The codes sets are unique and have different guidelines.
Inpatient coders review the entire medical record.
Outpatient coders focus on a particular date of service.
CMS inpatient reimbursement is based on IPPS which is determined by MS-DRGs
CMS outpatient reimbursement is based on OPPS and APCs

3. Inpatient Coding: Steps
Review Medical Documentation
Abstract procedure performed
Identify Min Term
Locate Term in the CPT Index
Verify Codes in the CPT Tabular Section
Determine the Need for Modifiers
Assign the Code

4. Outpatient: Steps in Coding
Locate the main term
Scan for Instructional Notes
Identify Terms that Modify the Main Term
Follow Any Cross-Reference Notes
Always Verify the Code in the Tabular List.

5. Inpatient Coding: Key Differences
Additional lengths of stay caused by hospital complications use the complication as the as the principle diagnosis
In an inpatient facility, medical coders must determine the principle diagnosis for the admission, as well as present on admission (POA) indicators on all diagnoses.
Uncertain diagnosis that are not documented at the time of discharge are not coded. Ex: “appears to be”
Medical/surgical procedures use ICD-10-PCS
Code assignment is based on entire admission

6. Outpatient Coding: Key Differences
Signs and symptoms are an acceptable for coding
Many outpatient procedures lack definitive diagnosis
Uncertain diagnosis in the Outpatient setting do not get assigned a code.
Coders can code up to absolute degree of certainty.
Code assignment is based on the encounter or visit
Medical/surgical procedures use CPT and HCPCS level II codes

7. Similarities between systems
Locating the correct code requires the following of certain steps.
Both require checking both the alphabetic index as well as the tabular section.
Guidelins must be followed in both systems.
These guidelines do however, provide a separate list of rules.