Inpatient and Outpatient Coding: Differences and Similarities, and How to Get the Most Out of Both Settings

Inpatient and Outpatient Coding: Differences and Similarities, and How to Get the Most Out of Both Settings

What is the difference between Inpatient and Outpatient coding? What are the similarities? And how can a healthcare facility streamline its processes to get the most out of both?

These may be some questions that health information management professionals ask themselves when they’re new to the field or undergoing a facility merger and acquisition. This article will address those questions and show you how YES HIM Consulting can assist your team with pain points in both Inpatient and Outpatient coding.

What are the main differences between Inpatient and Outpatient coding?

what is the difference between inpatient and outpatient

In the Inpatient setting, coders can assign codes for unconfirmed diagnoses. In the Outpatient setting, diagnoses must be confirmed in order to assign a code. Often, signs and symptoms are coded more frequently than a disease process for Outpatient coding. Outpatient coding is usually short and sweet.

In Inpatient coding, the circumstance of admission governs the selection of what is termed “principal diagnosis.” In Outpatient, the term “first listed” diagnosis is used instead of principal diagnosis.
Another main difference between Inpatient and Outpatient comes down to the payment systems. Inpatient utilizes the Inpatient Prospective Payment System (IPPS) and Diagnosis Related Groups (DRGs), while Outpatient operates in the Outpatient Prospective Payment System (OPPS) (CMS, 2022). Outpatient also employs the Ambulatory Payment System (APC).

Inpatient coding uses the Uniform Hospital Discharge Data Set (UHDDS) definition of principal diagnosis, which does not apply to Outpatient coding. Inpatient assigns Present On Admission (POA) indicators to each diagnosis code, while Outpatient does not (CMS, 2022).

What are the main similarities between Inpatient and Outpatient coding?

There are far more differences than similarities between Inpatient and Outpatient coding, but similarities do exist. Both Inpatient and Outpatient coding abide by AHIMA’s code of ethics. Additionally, both settings utilize ICD-10-CM for proper diagnosis code assignment.

Inpatient and Outpatient coders utilize resources and official coding guidelines, such as the American Hospital Association (AHA) Coding Clinic for ICD-9 & ICD-10-CM. Coders follow the ICD-9 Coding Clinic advice so long as a newer Coding Clinic doesn’t supersede the older advice. They also follow ICD-10-CM Official Guidelines for Coding and Reporting.

Furthermore, Inpatient and Outpatient coders follow the same basic technique to code a patient’s chart. They must review the medical record documentation to completely and accurately assign appropriate diagnosis and procedure codes. If documentation is missing that is pertinent to proper code assignment, the coder will hold the chart until the information becomes available in the medical record or issue a query to the physician.

What coding sets are used for Inpatient versus Outpatient coding?

For the most part, Outpatient uses Current Procedural Terminology (CPT) for procedures, while Inpatient utilizes ICD-10-PCS (AMA, 2022).

In the CPT code set, there are three levels. Level I covers medical services and procedures performed by physicians; it employs a numeric system. Level II identifies products, supplies, and other services not included in Level I; it employs an alpha-numeric system. Level III is a temporary set of codes for emerging technologies, services/procedures (CMS, 2022).

What are the main pain points with Inpatient and Outpatient coding?

Uncertainty of how to properly code a diagnosis and or procedure code can be a coding pain point. YES provides our internal team members with cutting-edge coding education. This same education is offered to our healthcare clients and partners.

Incomplete documentation is often another pain point. Complete documentation is required for proper code assignment of diagnosis and procedure coding. If pertinent information is not properly documented, it may warrant a query to the physician.

YES’ team of expert coding consultants understands the importance of proper code assignment from the very beginning. This decreases back-end denials and delays of payment. Our subject matter coding experts are ready to assist your facility with top-of-the-line coding support services.

If your facility is struggling with Professional Fee coding practices, review our advice and coding examples from Vanessa Youmans, COO.

YES helps clients get the most out of both Outpatient and Inpatient coding

YES HIM Consulting helps clients get the most out of their coding practices. We assist facilities by streamlining their daily coding assignments and prioritizing their needs to meet their monthly, quarterly, and/or yearly goals. Additionally, we relieve client stress caused by coding backlogs and staffing shortages.

Our credentialed coding professionals collectively have over 20 years of diverse expertise in the industry. We pride ourselves on openly communicating with clients to ensure their coding needs and goals are understood and met. You can trust YES HIM Consulting to be your reliable partner.

Kristie Thomas

Kristie Thomas, RHIT, CCS, CPC - Director, Outpatient Coding Services
what is the difference between inpatient and outpatient

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