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ICD-10-CM/PCS News Archives

Coders: Will ICD-10 make your job easier?

July 25, 2012:

With the industry transitioning to ICD-10-CM and -PCS, there is much discussion about how the new code set will benefit health care provider organizations and payers. These benefits focus largely on using more specific data to measure the quality, safety and efficacy of care, as well as improving clinical, financial and administrative performance. Yet, within all the discussions about ICD-10, few focus on how the implementation of the new code set may benefit coders.

From a coder's perspective, the greatly increased number of coding options within ICD-10 may seem overwhelming. As such, many coders are asking themselves if ICD-10 will make their jobs even more difficult, since they will have to select codes from such a vast library of options.

To be certain, there will be a learning curve for coders during the switch to ICD-10. However, coders will quickly discover a couple of the improvements within the new code set that will make their jobs easier. First, the improved structure of the new code set will enable a more intuitive pathway when selecting codes. Second, the increased specificity of ICD-10-CM will allow coders to better meet medical necessity requirements.

ICD-10-CM Structure
There are many similarities between ICD-9-CM and ICD-10-CM — such as the coding conventions that are used — so coders are not having to start from scratch when learning the new code set. The chapters in ICD-10-CM, however, are better organized than they were in ICD-9-CM. For example, neoplasms, which were previously scattered through ICD-9-CM codes, are now contained within the same chapter, and all neoplasm codes start with the letter C (think of "C" as in cancer, to remember neoplasm codes). Likewise, codes for obstetrics all start with the letter O, and diabetes mellitus codes start with the letter E (think of "E" as endocrine).

The coding structure in ICD-10-CM follows a logical pathway, so coding choices are often obvious when the proper documentation is present. One main difference with ICD-10-CM is that it allows for codes to be more specific, e.g. indicate laterality. The following example illustrates the differences of coding a primary malignant neoplasm of the lung using ICD-9-CM and ICD-10-CM. Using ICD-9-CM, the coding of the diagnosis is broken down by anatomic site. In contrast, ICD-10-CM takes this concept even further by providing the coder with options to identify which lung is affected — right, left, or unspecified (used when the side is not documented or the physician cannot be queried).

Malignant Neoplasm of Bronchus and Lung
Anatomic Site ICD-9-CM ICD-10-CM
Malignant neoplasm of main bronchus

Upper lobe bronchus of lung

Middle lobe bronchus or lung 162.4

Lower lobe bronchus or lung

Other parts of bronchus or lung

Unspecified site of bronchus or lung


In addition, note that the “unspecified” option for coding malignant neoplasm for the bronchus and lung remains in ICD-10-CM. The “other specified” option is available. However, in ICD-10-CM the code description for the other specified site is more specifically malignant neoplasm of overlapping sites – C34.8 Malignant neoplasm of overlapping sites of bronchus and lung.

In some cases, ICD-9-CM does not provide any further information concerning the anatomic site of the malignancy other than the general site. For example, malignant neoplasm of the liver is assigned to ICD-9-CM code 155.0. In ICD-10-CM, however, the coder would have approximately six choices to describe the specific anatomic site or type of liver cancer.

Malignant Neoplasm of Liver and Intrahepatic Bile Ducts
Anatomic Site ICD-9-CM ICD-10-CM
Liver, primary 155.0.
Liver cell carcinoma C22.0
Intrahepatic bile duct carcinoma C22.1
Hepatoblastoma C22.2
Angiosarcoma of liver C22.3
Other sarcomas of liver C22.4
Other specified carcinomas of liver C22.7
Unspecified type C22.8

Again the ‘unspecified’ and ‘other specified’ codes are available.

Using ICD-10-CM to Justify Medical Necessity
Although professional services are paid based on the procedure code, it's the diagnosis code that supports medical necessity requirements. The greater specificity of ICD-10-CM allows coders to make more accurate code selections to prevent claim rejections due to failing to meet medical necessity requirements.

In fact, many industry associations and experts predict that the use of ICD-10-CM will decrease the number of claims pended for medical necessity review, since there is less ambiguity in how procedure codes link to diagnosis codes. If the predictions hold true, reductions in medical necessity reviews will help coders reduce their workloads.

Currently, ICD-9-CM uses less specific codes, and conditions that support medical necessity for a particular service may also be classified to the same code as conditions that would not justify the service. This ambiguity is largely resolved with ICD-10-CM. Additionally, procedures involving new technologies can be more accurately linked to ICD-10-CM diagnoses codes, since the new code set offers a greater number — and more specific — choices for recent medical procedure innovations.

Key to meeting medical necessity requirements is becoming familiar with national coverage determinations (NCDs) from Medicare, and local coverage determinations (LCDs) from Medicare administrators. Although Medicare has released a limited number of NCDs for ICD-10-CM, coding professionals need to be on the lookout for upcoming releases as the industry gets closer to the ICD-10 implementation deadline.

Using ICD-10-CM in conjunction with the latest NCD and LCD updates will enable health care organizations to determine coverage of services upon patient scheduling or registration, in many cases. This will allow organizations to increase their compliance with the issuing of advance beneficiary notices (ABNs) to patients, as well as the issuing of commercial notices of non-coverage (NONC).

Assigning the proper diagnosis codes to comply with medical necessity requirements is largely dependent on having proper clinical documentation. Increased details within documentation will enable coders to obtain the maximum reimbursement for all the care that was delivered — while complying with medical necessity requirements. The greater specificity of ICD-10-CM will drive improvements in clinical documentation, prompting coders to work with clinicians to clearly record:

  • The impact of co-morbid conditions and complications
  • Why diagnostic tests were ordered
  • The severity of the patient's condition

Getting Ready for ICD-10
Learning to use ICD-10-CM presents a challenge for coders, but also offers opportunities. As coders begin using ICD-10-CM, they will experience the benefits of a more logically organized code set that will help them increase the efficiency and the accuracy of the work they perform.

To help with the transition, there are numerous informational and training resources that are available online, including:

In addition, Optum offers comprehensive training programs, consulting, and referential products here.


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