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ICD-9-CM Procedure Version 23 - icd 9 procedure code list

ICD-9-CM Procedure Version 23-icd 9 procedure code list

GEM Documentation and Users Guide 2007 version
Procedure Code Set General Equivalence Mappings
ICD-10-PCS to ICD-9-CM and ICD-9-CM to ICD-10-PCS
2007 Version
Documentation and User's Guide
Purpose and Audience
This document accompanies the 2007 update of the CMS public domain reference mappings of
the ICD-10 Procedure Code System (ICD-10-PCS) and ICD-9-CM Volume 3. The purpose of
this document is to give potential users the information they need to understand the structure and
relationships contained in the mappings so they can use them correctly. The intended audience
includes but is not limited to professionals working in health information, medical research and
informatics. General interest readers may find section 1 useful. Those who may benefit from the
material in both sections 1 and 2 include clinical and health information professionals who plan
to directly use the mappings in their work. Software engineers and IT professionals interested in
the details of the file format will find this information in Appendix A.
In This Document
For readability, ICD-9-CM is abbreviated "I-9," and ICD-10-PCS is abbreviated "PCS." The
network of relationships between the two code sets described herein is called the General
Equivalence Mappings (GEMs).
? Section 1 is a general interest discussion of mapping as it pertains to the GEMs. It
includes a discussion of the difficulties inherent in linking two coding systems of very
different design and structure. The specific conventions and terms employed in the
GEMs are discussed in more detail.
? Section 2 contains detailed information on how to use the GEM files, for users who will
be working hands-on with mapping applications now or in the future--as coding experts,
researchers, claims processing personnel, software developers, etc.
? The Glossary provides a reference list of the terms and conventions used, some unique to
this document, with their accompanying definitions.
? Appendix A contains tables describing the technical details of the file formats, one for
each of the two GEM files:
1) ICD-9-CM to ICD-10-PCS (I-9 to PCS)
2) ICD-10-PCS to ICD-9-CM (PCS to I-9)
GEM Documentation and Users Guide 2007 version
Section 1--Mapping and the GEMs
Mapping the ICD-9 and ICD-10 Procedure Code Sets
Mappings between ICD-9-CM and ICD-10-PCS attempt to find corresponding procedure codes
between the two code sets, insofar as this is possible. Because the two systems are so different,
translating between them the majority of the time can offer only a series of possible
compromises rather than the mirror image of one code in the other code set.
A sentence translated from English to Chinese may not be able to capture the full meaning of the
original because of fundamental differences in the structure of the language. Likewise, a
mapping may not be able to seamlessly link the codes in one set to identical counterparts in the
other code set, and this is especially true with I-9 and PCS. For these two procedure code sets, it
is actually rare to find two corresponding descriptions that are identical in level of specificity and
terminology used. This is understandable. Indeed, there would be little point in changing from
the old system to the new system if the differences between the two, and the benefits available in
the new system, were not significant.
There is no simple "crosswalk from I-9 to PCS" in the GEM files. A mapping that forces a
simple correspondence--each I-9 code mapped only once--from the smaller, less detailed I-9 to
the larger, more detailed PCS (a code set of entirely different design and scope) defeats the
purpose of upgrading to PCS. It obscures the differences between the two code sets and
eliminates any possibility of benefiting from the improvement in data quality that PCS offers.
Instead of a simple crosswalk, the GEM files attempt to organize those differences in a
meaningful way, by linking a code to all valid alternatives in the other code set. Generally
speaking, the entries in both the I-9 and PCS GEMs cannot simply point the user from one code
system to an identical counterpart in the other code system. This is because there is usually no
identical counterpart. The two coding systems are dramatically different on several fronts that
make it impossible to create a simple, all-purpose applied mapping.
It is important to understand the kinds of differences that need to be reconciled in linking coded
data. The method used to reconcile those differences may vary, depending on whether the data is
used for research, claims adjudication, or analyzing coding patterns between the two code sets;
whether the desired outcome is to present an all-embracing look at the possibilities (one-to-many
mapping) or to offer the one "best" compromise for the application (one-to-one mapping);
whether the desired outcome is to translate existing coded data to their counterparts in the new
code set ("forward mapping") or to track newly coded data back to what it may have been in the
previous code set ("backward mapping"), or any number of other factors. The scope of the
differences varies, is complex, and cannot be overlooked if quality mapping and useful coded
data are the desired outcomes. Several common types of differences between the code sets will
be examined here in detail to give the reader a sense of the scope.
GEM Documentation and Users Guide 2007 version
Procedure Codes and Differences in Structure
ICD-10-PCS is designed to avoid regional variants of code descriptions and "running out" of
code capacity. It contains a standardized vocabulary of surgical concepts, body part terms,
operative approaches, and so on, from which codes are built. For these reasons, mapping
between the two systems is often an "apples to oranges" enterprise.
The majority of the time, finding the "one correct" match in PCS coding concepts for a general
I-9 concept is not possible. Because it is standardized, PCS contains code elements describing
the precise objective of each coded procedure. Each of these concepts, called a "root operation,"
is defined in the system and can be used only when the procedure performed agrees with the root
operation definition. Further, because a word used by I-9 like "repair" does not precisely identify
a surgical method, the possible code alternatives in ICD-10-PCS must include all of the root
operations that could have been performed. This means that any initial mapping between the
systems must cast a wide net over possible equivalent options, options that can only be narrowed
down when a specific clinical scenario, use case, or other application has been defined.
For example, an ICD-9-CM code description containing the words "repair of aneurysm" does not
have a simple one-to-one correspondent in PCS. The I-9 description identifies the diagnosis of
aneurysm, (information which should already be captured on the record in the diagnosis code)
but does not actually give any indication of the specific method of repair. Depending on the
documentation in the record, the correct PCS code could be one of several root operations:
excision, replacement, or restriction, to name a few. All we know is that whatever is done to
"repair" an aneurysm is included in the I-9 code description.
Procedure Codes and Levels of Specificity
# of Characters 3-4 Numeric 7 Alphanumeric
# of Codes ~4,000 ~90,000
As shown in the table, PCS codes are longer, and there are many times more of them.
Consequently, in an unabridged I-9 to PCS mapping, each I-9 code is typically linked to more
than one PCS code, because each PCS code is more specific.
PCS is much more precise than I-9, and, just as important for purposes of mapping, the level of
precision in a PCS code is standardized across the system. In I-9, on the other hand, the level of
detail in a code varies greatly. For example, category 39, Other operations on vessels, contains
the codes:
39.31 Suture of artery
39.55 Reimplantation of aberrant renal vessel
The first code contains a precise description of the surgical technique (suture) but is very general
with respect to location (an artery somewhere). The second code does not specify the method of
reimplantation, but on other subjects is much more specific, containing a precise description of

What is ICD 9 coding used for?The ICD-9 was used to code and classify mortality data from death certificates until 1999, when use of ICD-10 for mortality coding started. a tabular list containing a numerical list of the disease code numbers in tabular form; a classification system for surgical, diagnostic, and therapeutic procedures (alphabetic index and tabular list).