Reader Question: ICD-9 Coding Specificity Is Not Just For Fun

Question: Endocrinology Coding Alert encourages diagnosis coding to the highest level of specificity possible. Why is it advantageous from our perspective to code 250.72 or 250.62 rather than 250.02 for a patient when ordering an A1C and other lab tests that carriers cover for any 250.xx code? It seems we are adding complexity to our coding ticket just to provide epidemiology data to the insurance company.

New York Subscriber

Answer: In the event of an audit, specific ICD-9 coding will show that your practice is making every effort to comply with coding guidelines. Diagnosis coding to the highest level of specificity is one of the basic rules of ICD-9 coding. CMS developed the ICD-9-CM coding guidelines, and providers should follow them simply because this is what CMS considers correct coding protocol.

As for reimbursement, while carriers may cover certain simple lab tests or other services for a patient with any 250.xx code, they may not cover some more complicated tests and services for a general 250.xx code and may require indication of a more specific condition. Rather than pick and choose when you can code general and when you must code more specific, it is best to consistently code to the highest specificity. This way you aren't asking coders to remember when they can and can't code general.

Also, consistently identifying a patient's specific condition paints a more accurate picture of the patient to carriers. You may look suspicious if you always code a patient with general diabetes, and then suddenly need to code more specific in order to recoup payment for a certain more complicated service.