NIH VS GCS Stroke Scoring

In the medical coding field, there is often confusion about when to report the National Institutes of Health Stroke Scale (NIHSS) and Glasgow Coma Scale (GCS) scores. Per FY2021 ICD-10-CM Official Guidelines for Coding and Reporting, a GCS score (R40.2-) is used in conjunction with traumatic brain injury to identify the severity of an acute brain injury. On the other hand, a NIHSS score (R29.7–) is used in conjunction with acute stroke codes (I63) to identify the patient’s neurological status and severity of the stroke.

Both scores are to be sequenced after the traumatic brain injury code (for GCS) or acute stroke code (for NIHSS).