The current method of diagnosis coding, International Classification of Diseases, 9th Edition, Clinical Modification/Procedure Coding System (ICD-9), has been used in the United States since approximately 1978. However, it contains outdated terminology and does not allow for updates in healthcare that have occurred in the 21st century. Due to these limitations, it has been mandated that all healthcare providers in the United States comply with the International Classification of Diseases, 10th Edition, Clinical Modification/Procedure Coding System (ICD-10 CM/PCS). Many countries around the world now utilize ICD-10 (and have done so for years) including Australia, France, Canada, Germany, the United Kingdom, and South Africa. The United States is one of the few countries that have not implemented this system.

On March 31, 2014 the US Senate voted to approve H.R. 4302, Protecting Access to Medicare Act of 2014. This included language delaying the implementation of ICD-10-CM/PCS by at least one year to October 1, 2015. ICD-10 fully replaced ICD-9 as of that date.

Advantages of ICD-10

The advantages of using of ICD-10 include (but are not limited to):

  • Increased specificity
  • Tracking public health
  • Improved ability to measure health care services
  • Increased accuracy in claims processing
  • Updated medical terminology
  • Added laterality

Differences Between ICD-9CM and ICD-10CM

ICD-9CM ICD-10CM
Approximately 14,000 codes Approximately 68,000 codes
3-5 digits 3-7 digits
First digit is alpha or numeric First digit is alpha only, second digit is numeric
Digits 2-5 are numeric Digits 3-7 are alpha or numeric
Decimal is used after the third character Decimal is used after the third character
19 chapters 21 chapters

Beginning on October 1, 2015, providers were no longer allowed to bill using ICD-9 codes. It is important to take the time to educate oneself about ICD-10 and determine what impact it will have on your practice. 

Anatomy of an ICD-10 Code

There are significant differences in the structure of an ICD-10 CM code versus an ICD-9 CM code. Below, you can find two examples of diagnoses, their corresponding ICD-10 CM code, and a description of what each digit means.

Diagnosis: Malignant neoplasm of right conjunctiva | Code: C69.01

C:  First digit of an ICD-10 CM code is alpha. Each chapter is assigned an alpha prefix. In Chapter 2 (Neoplasms), the diagnoses either have a “C” or “D” code assigned to them.

6:   Second digit is always numeric

9:   Third digit can be alpha OR numeric

0:   Fourth through seventh digits can also be alpha OR numeric

1:   Fourth through seventh digits can also be alpha OR numeric

Diagnosis: Cutaneous T-cell lymphoma, unspecified lymph nodes of head, face, and neck | Code: C84.A1

C:  First digit of an ICD-10 CM code is alpha

8:   Second digit is always numeric.

4:   Third digit can be alpha OR numeric.

AFourth through seventh digits can also be alpha OR numeric

1:   Fourth through seventh digits can also be alpha OR numeric

Finding an ICD-10 Code

Finding an ICD-10 Code is not much different than looking up an ICD-9 code, though you will be confronted by more choices. To prepare for the transition to ICD-10, you may want to consider purchasing an ICD-10 book. The book is available from a variety of sources such as the American Medical Association or the American Association of Professional Coders. This reference help you and your office staff to become familiar with the format of the code set and be able to learn how to navigate the system. You can also find the most recent draft of ICD-10 at the Centers for Disease Control website.

As with ICD-9, you will notice the book is divided into a tabular listing and an alphabetic listing of codes. The alphabetic listing, as its name implies, arranges the list of diseases and conditions in alphabetic order. If you are looking for the diagnosis code for “Leukemia” you would search for the term alphabetically. It will then correspond to an alphanumeric code, which you will then confirm in the tabular list. DO NOT select a code from the alphanumeric list, as it may not contain the appropriate level of detail necessary to report the code.

The tabular list is a numerical list of ICD-10 codes, grouped by chapter, categories, and subcategories. There are several notes at the beginning of the chapter. It is important to review these notes to ensure the selection of the appropriate code.

Here is an excerpt of the “Malignant neoplasms of eye, brain and other parts of the central nervous system” from the “ICD-10- CM Tabular List of Diseases and Injuries” (2013 draft). This example helps illustrate how to find an ICD-10 code.

Malignant neoplasms of eye, brain and other parts of central nervous system (C69-C72) Chapter Heading
C69 Malignant neoplasm of eye and adnexa Category (usually a three-digit code)

Excludes1:

malignant neoplasm of connective tissue of eyelid (C49.0)
malignant neoplasm of eyelid (skin) (C43.1-, C44.1-)
malignant neoplasm of optic nerve (C72.3-)

Excludes1: These conditions can not occur with the conditions listed above.
C69.0   Malignant neoplasm of conjunctiva Category (usually a three-digit code)
C69.00 Malignant neoplasm of unspecified conjunctiva
C69.01 Malignant neoplasm of right conjunctiva
C69.02 Malignant neoplasm of left conjunctiva
Subcategory: Four- to six-digit code; provides a higher level of classification

Organizations to Assist with the ICD-10 Transition

On March 31, 2014 the US Senate voted to approve H.R. 4302, Protecting Access to Medicare Act of 2014. This included language delaying the implementation of ICD-10-CM/PCS by at least one year to October 1, 2015. ICD-10 will fully replace ICD-9 as of this date.

The extra time should be used to its fullest advantage in terms of education and preparation. You don’t have to be a “victim” of ICD-10. This is a transition that can no doubt be daunting, but by planning ahead and taking the transition in pieces, it will seem less overwhelming. Several organizations offer free resources to assist with the transition.

Centers for Medical and Medicaid Services (CMS)

Features

  • Implementation timelines
  • Reference Guides
  • News
  • Up to date ICD-10 drafts
  • General Equivalence Mappings

World Health Organization (WHO)

Features

  • ICD-10 Downloads
  • Training program

Centers for Disease Control

Features

  • Up-to-date ICD-10 drafts
  • General Equivalence Mappings

Note: These products are not endorsed by ASCO and are just a few examples of organizations where you can purchase materials.