Though it may not be obvious to those unfamiliar with the subject, inpatient and outpatient coding have more than their share of differences. They have different guidelines, different codes, and different approaches, all of which means that they require different skillsets to master. Whether you are thinking of switching coding concentrations or you are simply starting out in the coding field and you aren’t sure which path to take, understanding the specifics of the two can help make sure that you choose the best path.

Outpatient coding, reimbursed under Medicare Part B, is used to report diagnoses services in which the patient does not stay at the medical facility long-term, which can include everything from conducting a blood test to treating a trauma patient in the emergency room. It uses the ICD-10-CM code set to report diagnoses and the CPT and HCPCS code sets to report services and their accompanying supplies. This side of coding cannot code using non-specific documentation such as “probable” or “suspected;” many providers, however, still use this sort of wording, which can often result in the need for queries.

On the other hand, inpatient coding, which is reimbursed under Medicare Part A, is used to report diagnoses and services where the patient must stay at the facility long term in order to recover and/or receive further treatment. Like outpatient coding, it also uses ICD-10-CM to track diagnoses, but it employs ICD-10-PCS to report procedures. Inpatient coding must identify a primary diagnosis and any secondary diagnoses in order to fulfill the necessary Medicare Severity-Diagnosis Related Groups, or MS-DRGs. This type of coding is widely considered to be the more advanced of the two, which in turn results in both a higher degree of difficulty and a more substantial pay.

Regardless of your path, make sure that you do all the proper research and talk to those who are already in the field so that you can be sure to choose the right type of coding for you.