International Classification of Diseases (ICD) translates medical conditions and diseases into a single format. The United States Department of Health and Human Services publishes their own indexed version of the ICD to include diagnostic and operative procedures, which at present is ICD-9-CM. The next version, ICD-10 utilizes alphanumeric codes that represent any known disease, condition, or circumstance.

The Centers for Medicare and Medicaid Services (CMS) is underway with implementation activities to convert from HIPAA Accredited Standards Committee (ASC) X12 version 4010A1 to ASC X12 version 5010 and National Council for Prescription Drug Programs (NCPDP) version 5.1 to NCPDP version D.0.

Some of the important dates in the implementation process are:

Jan 1, 2010	Payers and providers should begin internal testing of Version 5010 standards for electronic claims.
Dec 31, 2010	Internal testing of Version 5010 must be complete to achieve Level 1 Version 5010 compliance.
Jan 1, 2011	Payers and providers should begin external testing of Version 5010 for electronic claims. CMS begins accepting Version 5010 claims. Version 4010 claims continue to be accepted.
Dec 31, 2011	External testing of Version 5010 for electronic claims must be complete to achieve Level II Version 5010 compliance
Jan 1, 2012	All electronic claims must use Version 5010s. Version 4010 claims are no longer accepted.
Oct 1, 2013	Claims for services provided on or after this date must use ICD-10 codes for medical diagnosis and inaptient procedures. CPT codes will continue to be used for outpaitent services.

The new classification system provides significant improvements through greater detailed information and the ability to expand in order to capture additional advancements in clinical medicine. ICD-10-CM/PCS consists of two parts:

• ICD-10-CM – The diagnosis classification system developed by the Centers for Disease Control and Prevention for use in all U.S. health care treatment settings. Diagnosis coding under this system uses 3–7 alpha and numeric digits and full code titles, but the format is very much the same as ICD-9-CM; and
• ICD-10-PCS – The procedure classification system developed by the Centers for Medicare & Medicaid Services (CMS) for use in the U.S. for inpatient hospital settings ONLY. The new procedure coding system uses 7 alpha or numeric digits while the ICD-9-CM coding system uses 3 or 4 numeric digits.

Why an upgrade from ICD-9 to ICD-10:

• ICD-9-CM does not provide the necessary detail for patient’s medical conditions or the procedures and services performed on hospitalized patients.
• ICD-9-CM is 30 years old, has outdated and obsolete terminology, uses outdated codes that produce inaccurate and limited data, and is inconsistent with current medical practice.
• ICD-9 cannot accurately describe the diagnoses and inpatient procedures of care delivered in the 21st century.
• Many categories are full in the ICD-9 version and the system is not scalable to accommodate current procedures and practices.
• A more robust reimbursement version is needed to enhance accurate payment for the health services rendered by the provider.
• A need for a more flexible coding system which can quickly incorporate emerging diagnoses and procedures moving forward.

Structural Differences between the two coding systems:

ICD-9-CM	ICD-10-CM	ICD-10-PCS Procedure Codes
3-5 digits long	3-7 digits long	7 digits
13,000 Diagnosis Codes	68,000 Diagnosis Codes	87,000 Procedure Codes
First digit is alpha (E or V) or numeric and Digits 2-5 are numeric.	Digit 1 is alpha, Digit 2 is numeric; and Digits 3-7 are alpha or numeric (alpha digits are not case sensitive).	Each digit is either alpha or numeric (alpha digits are not case sensitive and letters O and I are not used to avoid confusion with numbers 0 and 1).
Examples: 496 – Chronic airway obstruction, not elsewhere classified (NEC); 511.9 – Unspecified pleural effusion; and V02.61 – Hepatitis B carrier.	Examples: A78 – Q fever; A69.21 – Meningitis due to Lyme disease; and S52.131a – Displaced fracture of neck of right radius, initial encounter for closed fracture.	Examples: 0FB03ZX – Excision of liver, percutaneous approach, diagnostic; and 0DQ10ZZ – Repair upper esophagus, open approach.

HIPAA 5010 and ICD-10
It is worth noting that the implementation for ICD-10 is heavily dependent on the transition of 4010 to version 5010 of the ANSI X12 standard for claims transactions. The 5010 standards will replace the existing 4010/4010A1 version of HIPAA transactions. .
CMS and HIT assert that it is absolutely essential that the 5010 platform be stable before the ICD-10 conversion. CMS office of HIPAA standards also claims that one cannot implement ICD-10 without 5010 from a technical standpoint. The conversion will require changes in coverage, dealings with health plans, and quality measurement; hospitals may also experience payment fluctuations. While 4010 relied heavily on workarounds and coding addenda, resulting in slightly different standards for each payer 5010 lends itself to more clarity and benefits. However realizing these benefits is dependent on fully implementing the standard and increasing provider usage of electronic transactions.