Common Coding Requirements
All claims must include the proper ICD-9-CM diagnostic code.
The Centers for Medicare and Medicaid Services (CMS) provides specific guidelines to aid in
standardizing U.S. coding practices. The guidelines for outpatient facilities, physician offices and
ancillary care are summarized below:
• Identify each service, procedure or supply with an ICD-9-CM code to describe the diagnosis,
symptom, complaint, condition or problem.
• Identify services or visits for circumstances other than disease or injury, such as follow-up
care after chemotherapy, with V codes provided for this purpose.
• Code the primary diagnosis first, followed by the secondary, tertiary and so on. Code any coexisting
conditions that affect the treatment of the patient for that visit or procedure as supplementary
information. Do not code a diagnosis that is no longer applicable.
• Code to the highest degree of specificity. Carry the numerical code to the fourth or fifth digit
when available. Remember, there are only approximately 100 valid three-digit codes; all other
ICD-9-CM codes require additional digits.
• Code a chronic diagnosis when it is applicable to the patient’s treatment or when follow-up on
the condition is requested during the visit.
• When only ancillary services are provided, list the appropriate V code first and the problem
second. For example, if a patient is receiving only ancillary therapeutic services, such as
physical therapy, use the V code first, followed by the code for the condition.
• For surgical procedures, code the diagnosis applicable to the procedure. If, after the procedure
has been done, the condition necessitating the surgery is more specifically identified, or even
determined to be different than the preoperative diagnosis, code the most specific diagnosis
determined to be the reason for the surgery.
Note – ICD-9 surgical procedures must be listed in Box 80 of the CMS -1450 or UB 04 claim form.