Where in the World Is ICD-10?
by Kathy Brouch, RHIA, CCS
|Where and how is ICD-10 being used? Learn how countries all over
the world have adapted to the newest version of this coding system
and how coders in the US can prepare for an eventual transition.
Are you ready for ICD-10? If you're a coder in the United States, you
don't have to be ready—yet. Though the implementation of the International
Statistical Classification of Diseases and Related Health Problems, Tenth
Revision, will not make waves here for a few more years, the new coding
system has been in place in some countries since 1994.
How is ICD-10 being used? Is it being modified? What has the transition
to a new coding system been like for coders worldwide? In this article,
we'll answer these questions.
ICD-10 is being implemented by World Health Organization (WHO) member
states for the coding of national mortality and morbidity statistics.
The most recent revision includes not only updated content but an expanded
scope—while its original purpose was to classify diseases and injuries,
the ICD-10 system allows users to code ambulatory care conditions and
risk factors often encountered in primary care.
It's been some time since the last ICD changeover occurred (generally
after 1975 when ICD-9 was published), and many elements of the coding
landscape have changed. For instance, ICD-10 is the first new diagnosis
coding system adopted since the widespread use of computers in healthcare.
The implementation of case mix systems such as diagnosis-related groups
(DRGs) in the United States and abroad brought the clinical coding profession
new recognition. Other worldwide changes in recent years, such as the
creation of a centralized coding authority, publication of national coding
standards, establishment of a maintenance process, and the certification
of clinical coders, all have complicated any transition to the 10th revision.
The Mortality/Morbidity Connection
The ICD system was originally intended to collect mortality data (data
on the reason for deaths) from governments worldwide. Accordingly, ICD-10
was first used for the coding of national mortality data. The Czech Republic,
Denmark, Romania, Slovakia, and Thailand implemented ICD-10 for mortality
coding in 1994, and since that time 33 additional countries have joined
The United States began using ICD-10 to code and classify mortality data
from death certificates in January 1999. The conversion from ICD-9 to
ICD-10 had an effect on coders and the mortality data system as a whole,
including the revision of instruction manuals and development of new medical
software to replace the manual coding process. To that end, the National
Center for Health Statistics (NCHS) created special software to automate
coding of medical information on the death certificate, according to WHO
In addition, the states and NCHS developed standard data collection and
model procedures for the uniform registration of events (i.e., mortality
data) by states. Instructional materials were also made available to make
it easier to properly complete a death certificate.
In the sixth revision to ICD, codes were added to allow for the collection
of data for morbidity statistics (for non-fatal diseases, injuries, or
health-related problems). This extension has continued with subsequent
revisions, including ICD-10. But implementation of ICD-10 for morbidity
coding has been slower, with only two countries using it for this purpose
in 1994 and 13 coming on board after 1996.3
(See chart below.)
Currently, an implementation date for morbidity data reporting in the
United States has not been scheduled. The uncertainty is partly a result
of the Health Insurance Portability and Accountability Act (HIPAA), which
mandates a specific process for the designation of coding standards. The
initial recommendation for coding standards includes ICD-9-CM, given that
a clinical modification to ICD-10 is under development. Once the first
set of standards is in place, a new phase of public hearings is required,
along with publication of a notice of proposed rulemaking and a final
notice for any changes to occur.
The NCHS has stated that once the final notice indicating ICD-10-CM as
a coding standard is published, the industry will have 24 months to prepare
for the switch.
What if the system needs to be modified between revisions? For the first
time since its initial publication, a process has been developed for ICD
to be modified between revisions.
All proposals for changes to ICD-10 must be sponsored by one of the
nine Collaborating Centres for Classification of Disease (for the United
States, the centre is the NCHS) and submitted based on a timeline tied
to the annual meeting of centre heads. If the modification is accepted,
both WHO and the nine centres are responsible for distribution. Implementation
would coincide with the annual updating cycle established by the centre
but would be no later than the beginning of the calendar year commencing
15 months after each centre head meeting.
WHO also has authorized the development of adaptations of ICD-10 under
specific requirements. All modifications to the ICD-10 must conform to
WHO conventions for the ICD. Authorization to develop an adaptation of
ICD-10 for use in the United States for government purposes has been received
Since its seventh revision, the United States has clinically modified
ICD. Not surprisingly, a clinical modification for ICD-10 for morbidity
purposes is in the works in the United States. The revision included recommendations
from a technical advisory panel as well as help from physician groups,
clinical coders, and others to ensure clinical appropriateness and function.
An initial draft of the tabular list of ICD-10-CM and preliminary crosswalk
between ICD-10-CM and ICD-9-CM were published for public comment in December
1997. Since that time, comments from various organizations and individuals
have been under review. Availability of ICD-10-CM is not expected until
Once the tabular list and alphabetic index are complete, educational
materials, training programs, and final crosswalks between ICD-9-CM and
ICD-10-CM will be finished. The NCHS plans to conduct a comparability
study to help users of data distinguish between real changes in utilization
by diagnosis and changes that are result of changes to the classification
The United States is not the only country that has received permission
from WHO to modify ICD-10. After a study by the National Coding Centre
(NCC), currently known as the Australian National Centre for Classification
in Health (NCCH), the NCC began the development of an adaptation of ICD-10
in July 1995.5 It also took on the creation
of a procedure classification, because ICD-10 does not include one. In
addition, the NCCH also developed a set of Australian coding standards,
incorporating those already in place for the Australian edition of ICD-9-CM.
The result of all this effort was the first edition of ICD-10-AM, published
as a five-volume set in 1998 and comprising the Australian modifications
to the ICD-10, the procedure classification, and the Australian national
coding standards. In July 1998, the first edition of ICD-10-AM was implemented
in certain states, and the remainder came on board in July 1999. The NCCH
has completed a second edition of ICD-10-AM, which was scheduled to be
introduced in July 2000.
Ties to Case Mix Systems
In the United States, since the advent of DRGs in 1983, ICD-9-CM codes
have determined reimbursement on individual inpatient hospital cases.
As a result, US coders have seen these developments:
- a group that has the responsibility for development of coding guidelines,
i.e., the cooperating parties
- Coding Clinic for ICD-9-CM, published by the American Hospital Association,
the official clinical coding guidelines resource
- the ICD-9-CM Coordination and Maintenance Committee, which is in
charge of updating ICD-9-CM
- clinical coder certification
Only one country—Australia—has undergone a similar evolution.
Australia's healthcare data has been coded in ICD-9-CM since the mid-1980s.
After the adoption of ICD-9-CM, the country implemented a case mix system,
the Australian National Diagnosis Related Groups (AN-DRGs). Like the United
States, Australia also has a national coding center, published coding
standards, a maintenance process for revisions to the classification system,
and a certification program for coders.
Making the Transition to ICD-10
For some countries, making the transition from the 9th to the 10th ICD
revision has been more complex because of changes (like those outlined
above) that have occurred as a result of the ICD link to case mix systems.
As Australia found, the transition involved not only developing the modification
but creating various crosswalks, revising existing coding guidelines,
and designing educational materials for the introduction of ICD-10-AM.
For example, under the guidance of the NCCH, mappings were developed
between ICD-9-CM and ICD-10 and vice versa. With the advent of ICD-10-AM,
the final maps were used to develop specifications for the fourth version
of AN-DRGs, now known as Australian Refined Diagnosis Related Groups (AR-DRGs).6
In all probability, the United States will do something similar to create
a version of DRGs based on ICD-10-CM and data comparability. It is expected
the Health Care Financing Administration will unveil its plans for this
process once ICD-10-CM is published in its final form and is recognized
as a coding standard under HIPAA.
While most countries have not developed a clinical modification to ICD-10,
changes that have taken place since the transition to the 9th ICD revision
have still affected the transition to ICD-10. In fact, many countries
have created new reporting requirements and put into place national coding
policies along with the implementation of ICD-10.7
For instance, the United Kingdom (UK) National Health Service's (NHS)
established the Centre for Coding and Classification (CCC). In 1990 the
CCC became a part of the Loughborough section of the NHS Information Authority
and then in 1996, together with the Office for National Statistics (ONS),
it became the joint World Health Organization Collaborating Centre for
the Classification of Diseases, UK.8 In
April 1999, the NHS Centre for Coding and Classification was incorporated
into the NHS Information Authority.
The accountability for the morbidity classification within the UK lies
with the NHS Information Authority (Loughborough) and the mortality classification
is found within the ONS. ICD-10 codes are currently mandatory for use
across England for the recording of diseases and health-related problems,
i.e., the diagnosis or reason for a patient episode of care within the
acute sector of the National Health Service.
In addition, national clinical coding standards as agreed by the UK Coding
Review Panel were developed to ensure consistent and comparable data.
These are published in the NHS Executive Clinical Coding Instruction Manual,
ICD-10 and OPCS-4, and the Coding Clinic insert of the Data Quality Review
Training Requirements: The Final Step
As one would expect, training for any new system requires a well-thought-out
plan. Australia's began with the formation of an ICD-10-AM education working
party in November 1995, a little more than 2.5 years before implementation
in the first group of states.
In general, to ensure the effectiveness of the training of staff who
will be doing the actual coding on the specifics of the 10th revision,
training has occurred no sooner than six months prior to the actual implementation
Training is one of the key elements in a process that is, as we've seen,
more involved than previous coding system conversions. As coding and working
with healthcare information become increasingly computerized, the processes
will become increasingly complex. As the United States moves closer to
making the switch, we would do well to learn from the successes and failures
of our counterparts worldwide.
1. "Implementation of ICD-10 by WHO Member States." World Health Organization
home page. Available at www.who.int/whosis/icd10/implemen.htm.
2. "Mortality Data from the National Vital Statistics System." National
Center for Health Statistics home page. Available at www.cdc.gov/nchs/about/major/dvs/im.htm.
3. "Implementation of ICD-10 by WHO Member States."
4. "International Classification of Diseases, Tenth Revision, Clinical
Modification." National Center for Health Statistics home page. Available
at http://www.cdc.gov/nchs/ about/otheract/icd9/abticd10.htm.
5. Innes, Kerry, Karen Peasley, and Rosemary Roberts. "Ten Down
Under: Implementing ICD-10 in Australia." Journal of AHIMA
71, no. 1 (2000): 52-56.
7. Law, Jeanne. "Implementing ICD-10 Will Require Education, Support
and Commitment." Advance for Health Information Professionals
5, no. 8 (April 17, 1995): 14Ð15.
8. "Coding and Classification." NHS Information Authority home page.
Available at www.coding.nhsia.nhs.uk/.
10. Law, Jeanne. "What's Happening with ICD-10?" Second Annual Conference
on Improving Clinical Data Bases for Health Policy Development, 1997.
11. "Copyright Information." World Health Organization home page. Available
at www.who.int/whosis/icd10/copy righ.htm.
Kathy Brouch is manager of volunteer services at AHIMA. Her e-mail
address is firstname.lastname@example.org.
Brouch, Kathy. "Where in the World Is ICD-10?" Journal
of AHIMA 71, no. 8 (2000): 52-57.