Question:
Does Medicare offer guidance related to when unspecified diagnosis codes are appropriate?
Answer:
Yes, in a MLN booklet on general equivalency mappings (GEMs), the Centers for Medicare & Medicaid Services (CMS) provide the following information.
Sign/symptom and unspecified codes have acceptable, even necessary, uses. While you should report specific diagnosis codes when they are supported by available medical record documentation and clinical knowledge of the patient’s health condition, in some instances signs/symptoms or unspecified codes are the best choice to accurately reflect the health care encounter. You should code each health care encounter to the level of certainty known for that encounter.
If a definitive diagnosis has not been established by the end of the encounter, it is appropriate to report codes for sign(s) and/or symptom(s) in lieu of a definitive diagnosis. When sufficient clinical information is not known or available about a particular health condition to assign a more specific code, it is acceptable to report the appropriate unspecified code (for example, a diagnosis of pneumonia has been determined but the specific type has not been determined). In fact, you should report unspecified codes when such codes most accurately reflect what is known about the patient’s condition at the time of that particular encounter. It is inappropriate to select a specific code that is not supported by the medical record documentation or to conduct medically unnecessary diagnostic testing to determine a more specific code.