FAQ 1.  What is ICD-10-CM?

ICD-10-CM is the long awaited diagnosis code set revision to ICD-9-CM.  There is another code set known as ICD-10-PCS (Procedure Coding System).  ICD-10-PCS will be discussed in FAQ 6 below.

The International Classification of Diseases (ICD) is the copyrighted official publication of the World Health Organization (WHO) and is part of the WHO family of classifications (which includes International Classification of Functioning, Disability and Health, International Classification of Health Interventions and International Classification of Diseases for Oncology). The primary purpose of ICD is for epidemiological tracking of illness and injury. ICD has been used in the US since 1949 (ICD­6). The first formal US adaption was by the US Public Health Service with ICD­7. The current US adaptions are controlled by the “cooperating parties”: National Center for Health Statistics/CDC (NCHS), Centers for Medicare and Medicaid Services (CMS), American Hospital Association (AHA), and American Health Information Management Association (AHIMA).

Until recently, WHO revised ICD every 8-10 years. The US version of ICD-9 (ICD-9-CM [clinical modification]) has been in use since 1979. ICD-10 was approved by the World Health Assembly in 1989 and released for use in 1994. It is currently used by a majority of countries. The US has been using ICD-10 for mortality statistics since 1999.

FAQ 2.  What is the implementation date for ICD-10?

On January 16, 2009, the Department of Health and Human Services released the HIPAA Administrative Simplification: Modifications to Medical Data Code Set Standards to Adopt ICD-10-CM and ICD-10-PCS Final Rule (CMS-0013-F). At this writing, the scheduled compliance date for implementation of the ICD-10-CM/PCS Coding System is October 1, 2014 for all covered entities.

FAQ 3.  Why do we need ICD-10-CM?

Frankly, ICD-9-CM is running out of codes. Hundreds of new diagnosis codes are submitted by medical societies, quality monitoring organizations and others annually. ICD-10-CM will allow not only for more codes but also for greater specificity and thus better epidemiological tracking. This will allow providers to better identify certain patients with specific conditions that will benefit from tailored disease management programs, e.g. diabetes, hypertension, asthma.

FAQ 4.  How are ICD-9 and ICD-10 different?

The ICD-10-CM codes are very different from those currently used in ICD-9-CM. All codes in ICD-10-CM are alpha-numeric. There may be up to seven alpha-numeric characters, requiring billing software program changes to accommodate the additional digits, as well as extensive coder training. ICD-10-CM will have greater specificity (i.e. granularity) along with laterality (anatomic location). Specialty societies had significant input in the development of the depth of detail they wanted to enable the tracking of certain conditions and injuries.  Given the increased level of coding specificity required by ICD-10, it is anticipated the degree of documentation required by physicians will also increase.

ICD-10-CM codes will be able to provide more in depth information about the patient's condition that can be more easily captured in an electronic medical record. Physician (HCFA 1500) and hospital (UB-04) billing forms have been updated to accommodate the changes. 






Precordial Chest Pain



Asthma, Acute Exacerbation



Thumb laceration      
Thumb, w/o nail damage, initial encounter



Laceration w/o FB, right thumb, initial encounter


Laceration w/o FB, left thumb, initial encounter


Laceration w/o FB, unspecified thumb, initial encounter


*Just as with ICD-9-CM, clear physician documentation will be important to aid in assigning appropriate ICD-10-CM codes.

FAQ 5.  What is GEM?

General Equivalence Mappings (GEM) were developed by NCHS and CMS, with collaboration of AHIMA and AHA, as a tool to assist with the conversion from ICD-9-CM codes to ICD-10-CM and the conversion of ICD-10-CM codes back to ICD-9-CM. The GEMs are forward and backward mappings between the ICD-9-CM and ICD-10-CM coding systems and are used to help develop crosswalks that provide important information linking codes of one system with codes in the other.

In some instances, there is not a translation between an ICD-9-CM code and an ICD-10-CM code. When there is no plausible translation from a code in one system to a code in the other system, a "No Map" flag indicator is noted.

FAQ 6.  What is ICD-10-PCS?

ICD-10-PCS (Procedure Coding System) is currently designated to replace Volume 3 of ICD-9-CM for hospital inpatient use. The cooperating parties and especially CMS have made it very clear that there is no intention for ICD-10-PCS to in any way, shape or form to replace CPT for the identification of physician work. Its only intention is to identify inpatient facility resource utilization in a way not directly related to physician work but directed towards allocation of hospital services.

CPT remains the procedure coding standard for physicians, regardless of whether the physician services were provided in the inpatient or outpatient setting. Any third party payer asking for Volume 3 procedure codes to be submitted along with CPT codes for outpatient services is in violation of HIPAA regulations and subject to fines by CMS.

Some preliminary inpatient hospital testing of ICD-10-PCS has indicated that the new procedure coding system is problematic to learn for both experienced and inexperienced coders.

FAQ 7.  What are the estimated costs for adopting the new ICD-10 coding systems?

There have been many questions as to the cost of implementing ICD-10. The RAND Science and Technology Policy Institute is publishing its findings on the cost and benefits of implementing ICD-10. According to the draft executive summary, providers will incur costs for computer reprogramming, the training of coders, physicians, and code users, and for the initial and long-term loss of productivity among coders and physicians. The cost of sequential conversion (10-CM then 10-PCS) is estimated to run $425M to $1.15B in one-time costs plus somewhere between $5 and $40 million a year in lost productivity.

RAND assumes the benefits as largely coming from the additional detail that ICD-10-CM and ICD-10-PCS would offer. The benefit of more accurate payments to hospitals for new procedures ranges from $100M to $1.2B. Benefits from fewer rejected claims would be $200M to $2.5B and $100M to $1B for fewer exaggerated claims. The identification of more cost-effective services and direction of care to specific populations would result in a benefit of $100M to $1.5B. This is in addition to any benefits that would come from better total disease management and better directed preventive care.

Blue Cross and Blue Shield sponsored a study to determine costs to the health care industry in adopting ICD-10-CM and ICD-10-PCS. The study indicated a cost range of $5.5-13.5 billion for systems implementation, training, loss of productivity, re-work, and contract re-negotiations during a 2-3 year implementation period. Over half of the costs would be borne by health care providers. Long term recurring costs for loss of productivity were estimated at $150 million to $380 million. However, both hospitals and third party payers have already made extensive investments in preparation for the October 1, 2014 scheduled change over. 

FAQ 8.  Where can I learn more about ICD-10-CM and ICD-10-PCS?

Copies of the latest version of ICD-10-CM, ICD-10-PCS and the GEMs may be downloaded for free from the NCHS and CMS websites. 



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