Coding: Your Top Coding Concerns Solved

October 1, 2008

This issue: How to improve your ICD-9 coding.


If you are seeing a lot of denials for medical necessity, look at your ICD-9 coding. Following some basic rules can improve things immensely.

Start by looking at the rules in the Official Guidelines for Coding and Reporting found in the front of most ICD-9 manuals. In Section IV, Diagnostic Coding and Reporting for Outpatient Services, it says: “List first the ICD-9 code for the diagnosis, condition, problem, or other reason chiefly responsible for the services provided.”

Don’t over-simplify this. It doesn’t say “code the reason for the visit.”

It says what it says; code whatever is “chiefly responsible for the services provided.” That is the underlying condition, not necessarily the current signs and symptoms.

For example, say a patient presents for hemoptysis, which results from their esophageal varices. This is often driven by cirrhosis of the liver, and that’s what will be coded first - the cirrhosis, the underlying condition that “is chiefly responsible for the problem” - not the soup of the day symptom, the hemoptysis.

The next subsection tells us to “Code all documented conditions that coexist at the time of the encounter/visit, and require or affect patient care, treatment or management.

Careful here; this is where Medicare wants to see only those conditions that are either being managed actively - or those whose presence influences the treatment or management of the problem at hand. Don’t just report everything the patient has or has had! The very next sentence says “Do not code conditions that were previously treated and no longer exist.”

Other related rules:

  • If the practitioner has not yet established a diagnosis, code the documented symptoms/signs

  • A sign/symptom may be reported as the first listed code if a physician has not made a definitive diagnosis

  • If the practitioner has established a diagnosis, assign the code(s) for the encounter based on the established diagnosis (or diagnoses

  • Do not code related signs/symptoms as additional diagnoses if the signs/symptoms are integral to the first listed code

  • Additional signs/symptoms that are not integral to a disease process may be reported separately

Avoiding common ICD-9 errors

Everyone sort of knows to select diagnosis codes to their highest level of specificity, using the 4th or 5th digit.

However, quite often, physicians just don’t provide the required information. Some of these lapses may impact payment, some may not. But if you aren’t paying attention, it is quite likely you are losing money based on “medical necessity” denials.

It’s not so much the obvious actual presence of a 4th or 5th digit. Most office software or billing packages should be smart enough by now to flag incomplete codes before the claim is submitted.

It is really about how much information is provided. Take diabetes. The first three numbers are easy: 250.xx. The 4th digit is about what other organ systems are impacted by the diabetes, and the 5th digit specifies the type of diabetes and the control or lack thereof.

But how many people just code 250.00 for everything? The first zero indicates that there are no other organ systems impacted or involved, and the second indicates that it is Type II or an unspecified type diabetes not stated as uncontrolled. Is it always like that? I don’t think so, but many providers just ship out the most nonspecific version of the code.

Did you know that even for the 250.00 version, the most basic, if the patient is a long-term insulin user currently on insulin that you must also report code V58.67 in addition to the 250 series code? You would if you read the fine print in the 5th digit section of ICD-9.

You need to know when multiple ICD-9 codes are needed to accurately represent an encounter or service. This requirement occurs more than you may think.

For many hypertension codes with renal involvement you’ll now need additional codes from the 585 series that represent the stage of Chronic Kidney Disease, and more of these are coming every year as medical knowledge and coding tools are honed.

So learn specificity and other ICD-9 rules. Just because these codes don’t direct physician payments as directly as CPT does is no reason not to be accurate.

Bill Dacey, CPC, MBA, MHA, is principal in the Dacey Group, a consulting firm dedicated to coding, billing, documentation, and compliance concerns. Dacey is a PMCC-certified instructor and has been active in physician training for more than 18 years. He can be reached via editor@physicianspractice.com.

This article originally appeared in the October 2008 issue of Physicians Practice.