Seventh Character Application for Injuries in the Principal Diagnosis and the Impact to Data Quality

Seventh Character Application for Injuries in the Principal Diagnosis and the Impact to Data Quality

This monthly blog highlights and discuss emerging trends and challenges related to healthcare data and its ever changing life cycle.

By Kathleen E. Wall, MS, RHIA

By now, we’ve all had practice assigning 7th characters for injuries. And, by now, we all know that in theory the guidance seems very clear—but the application of this new concept is not clear at all. Why is there so much confusion and why does it matter? What are the short- and long-term implications on data quality and analytics due to incorrect assignment? For the sake of this blog, we will only discuss the impact of applying the 7th characters “A” or “D” in the principal diagnosis slot because correct assignment of these characters is not only important for appropriate MS-DRG assignment and reimbursement (short-term), but also for the long term collection of data related to the continuum of care, acuity and costs associated with injuries and expected outcomes.

The confusion comes from the terminology used in the definition of “initial” vs. “subsequent” episodes of care. When you read the actual explanation of the characters, the terminology used in the explanation has very little to do with “initial” vs. “subsequent” visits. It has everything to do with whether or not the patient is receiving “active treatment” or “routine follow-up care.” So think about this: when would a patient ever be admitted to the acute care setting (hospital inpatient) for routine follow-up care as the principal diagnosis? When would a cast change or an x-ray or medication adjustment or follow up visit meet medical necessity for admission to an acute care inpatient hospital setting?

With only one exception, NEVER is the correct answer. The one exception is located in the “subsequent episode of care” definition: if a patient is admitted for planned or routine removal of an internal fixation device, only then would the “D” be used in the principal diagnosis slot. Even so, most of these patients would likely receive care in the outpatient care setting. The key words here are “planned or routine” removal. If there are any complications such as pain, loosening, displacement, or breakage of the internal fixation device, the complication of device codes would be used with the 7th character of “A.” The definitions, according to the ICD-10-CM Guidelines for Coding and Reporting are:

  • 7th character “A” (initial encounter) is used as long as the patient is receiving active treatment for the condition. Examples of active treatment include surgical treatment, emergency department encounter, evaluation, and continuing treatment by the same or a different physician.
  • 7th character “D” (subsequent encounter) is used for encounters after the patient has completed active treatment and is receiving routine care for the condition during the healing or recovery phase. Examples of subsequent care, according to a fact sheet from Anthelio Healthcare Solutions, are: cast change or removal, an X-ray to check healing status of fracture, removal of external or internal fixation device (planned or routine—not if there is a complication), medication adjustment, and other aftercare and follow up visits following treatment of the injury or condition.


So what can we do to study the impact of incorrect 7th character assignment? In data analytics, it is sometimes difficult to know where to focus our efforts, or even to find the “low hanging fruit” as we get started. But in this case, there is an easy analysis: look for MS-DRG assignment of DRGs 939-941 (O.R. PROC W DIAGNOSES OF OTHER CONTACT W HEALTH SERVICES W MCC, W CC AND W/O CC/MCC). These are the DRGs where the 7th character of “D” would be assigned to the injury as the principal diagnosis and surgical treatment would have been performed during the stay. The error rates revealed in these studies can be quite high—even as high as 100 percent.

The long term impact of incorrect 7th character assignment is the inability to perform research studies related to costs and outcome of injuries as well as the impact to the continuum of care of patients in the different care settings. With the implementation of ICD-10-CM, the uniqueness of these additional data elements provided for tracking patients throughout a continuum of care requires us to be proactive in our analysis so that when the long term plan for analyzing and utilizing this data is implemented, we are ready with accurate data.


Kathleen E. Wall ( is compliance and quality auditor at himagine solutions, inc.

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  1. Very confused about that 7th character , what about S(sequela). How do you know when to use it.

  2. Very confused about that 7th character , what about S(sequela). How do you know when to use it.

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