Low Hanging Fruit: 4 Easy-to-Avoid Coding Mistakes

Medical coding is a challenge, but a dose of caution will help you to avoid many of the most common coding errors. Here are four areas to watch.

1. Keep current

The AMA updates its CPT® codebook, annually. Each new year brings hundreds of changes, including new and revised codes, new and revised coding guidelines, code deletions, and more. HCPCS codes and Medicare National Correct Coding Initiative (NCCI) edits receive several updates, each year. The CMS issues new or revised coding guidelines practically every week. And although the ICD-9-CM code set has seen minimal changes, in recent years, the scheduled implementation of ICD-10-CM will mean an entirely new set of codes to apply (and continued updates, as well).

The bottom line is: If you're using outdated coding resources, you stand a very good chance of applying defunct codes, or otherwise reporting services and diagnoses incorrectly.

2. Avoid truncated codes

Always select codes to describe the patient's condition to the highest degree of specificity supported by documentation.

All ICD-9-CM diagnosis codes require at least three digits. For added specificity, some diagnostic categories require a fourth, or a fourth and a fifth, digit. Symbols throughout the tabular section of the ICD-9-CM manual identify when a code requires a fourth or fifth digit. When fourth and fifth digits are required, the additional digit options may be presented as sub terms, or at the beginning of the three-digit category.

Example: Check fifth digit

575.1 Other cholecystitis

575.10 Cholecystitis, unspecified

575.11 Chronic chlolecystitis

575.12 Acute and chronic cholecystitis

Failing to assign a fourth or fifth digit, when required, will result in claims rejected for lack of medical necessity or supporting diagnosis.

The ICD-10-CM code set, which is scheduled to replace ICD-9-CM on Oct. 1 of this year, contains codes with up to seven (alphabetic and numerical) characters, and ups the ante for diagnostic specificity. As is the case with ICD-9-CM, the use of truncated (i.e., incomplete) ICD-10-CM codes will result in denied or delayed claims.

Note that the relevant detail available in the provider's documentation is crucial to selecting a precise, appropriate diagnosis code.

3. Read the whole note

The coder should review the provider's entire progress or operative note to be sure no reportable services are missed. Improper code selection also may result if you code from documentation headers instead of reading the note in its entirety. For example, the operative report header may list the "expected" procedures, but the body of the note may record a more extensive or entirely different procedure due to unforeseen circumstances. Or, the body of the note may contain diagnostic information that helps the coder to select a more precise diagnosis code.

4. Distinguish new vs. established patients

Many E&M service codes distinguish between "new" and "established" patients. A patient is new if he has not received a face-to-face, professional service from the provider, or a provider of the same specialty/subspecialty in a group practice, within the previous 36 months. This is commonly known as the "three-year rule."

Where the patient is seen is not a factor in determining new vs. established. For example, Mrs. Jones' general practitioner, Dr. Smith, joins a new group practice across town. As long as Dr. Smith has seen Ms. Jones within the past three years, she is an established patient at the new location. Likewise, if a physician has provided services face to face with a patient in the hospital, and sees the same patient in her office within three years, the patient is established.

If another member of the group has seen the patient for a different problem within the past three years, but that provider is of a different specialty/subspecialty, you might still report a new patient service. For instance, a patient consults with an orthopedist for possible hip replacement. The patient saw an internist in the same group practice several times in the past three years. In this case, the patient is new to the orthopedist, but established for the internist. For a list of Medicare-recognized physician specialties, check the CMS Web site.

Only face-to-face services count toward a patient's new or established status. CPT's® E&M Services Guidelines stress, "Solely for the purposes of distinguishing between new and established patients, professional services are those face-to-face services rendered by a physician and reported by a specific CPT® code(s)." A patient is new, for instance, if the physician interpreted test results a month earlier, but had provided no face-to-face services to the patient within the previous three years. CMS Transmittal R731CP, Change Request 4032 affirms this, stating, "An interpretation of a diagnostic test, reading an X-ray or EKG, etc., in the absence of an E&M service or other face-to-face service with the patient does not affect the designation of a new patient."