ICD-9-CM vs. ICD-10?
First, let's get straight what exactly we're talking about. Currently, we use the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) to report diagnoses and hospital inpatient procedures. ICD-9-CM is divided into three volumes:
- Volume 1 - Tabular list of diagnosis codes (lists all codes with their descriptions)
- Volume 2 - Index of diseases
- Volume 3 - Tabular list and index of procedures
It seems logical, then, that ICD-10-CM will replace ICD-9-CM, but it's only partially true. The diagnosis portion of ICD-10 is part of the clinical modification (ICD-10-CM) and the procedure portion is part of ICD-10-PCS (Procedure Coding System). In order to simplify, some articles will refer to the system collectively as ICD-10 or ICD-10-CM/PCS. When it comes time for training, though, you want to make sure you are getting trained in both CM and PCS if you plan to work as a hospital inpatient coder.
I've often been asked if it's such a big deal to switch why we don't just stick with ICD-9-CM. There are many reasons for making the switch to ICD-10, but here are the main reasons:
- ICD-10-CM/PCS offers better specificity in reporting diagnoses and procedures
- The US is the only G7 nation that does not use a version of ICD-10, which makes comparing data worldwide difficult
- The structure of Volume 3 ICD-9-CM codes does not allow for proper expansion of the code set in order to report new technologies
When the proposed rule announcing implementation of ICD-10 was released, there was a lengthy discussion about the possibility of replacing CPT with ICD-10-PCS. Researchers determined, however, that the two coding systems were developed for different purposes, which did not make them interchangeable. CPT was developed originally to report physician services while ICD-10-PCS was developed for hospitals. The use of CPT will not be impacted by implementation of ICD-10-PCS and it will still be required for reporting on physician and outpatient hospital claims.
How Different is ICD-10?
While the general format and look of the ICD-10-CM tabular section doesn't look too different from ICD-9-CM, the codes themselves do. Existing ICD-9-CM code format is 3-5 numeric digits, except in the case of V and E codes. ICD-10-CM codes have 3-7 alphanumeric characters. To me, the codes look more like license plate numbers! The method of looking up a code is similar to ICD-9-CM - you locate the main term in the index, consult the secondary entries, and then consult the tabular listing to confirm code assignment.
ICD-10-PCS codes are very different from ICD-9-CM procedure codes. Coding in ICD-10-PCS understands a great understanding of the procedure performed, as the main index term is the root operation rather than the eponym or name of the procedure. For example, there is no term in the ICD-10-PCS index for "Whipple procedure." The coder must know which of the major root operations this falls under and code appropriately. Once the procedure is located in the index, the coder will find only the first 3-4 of the total 7 character code listed. Those first characters will lead the coder to tables, not a tabular list, that allows for building the rest of the code.
Who Will be Affected Most?
There is much debate about who will be most affected by implementation of ICD-10. For physician offices, although physicians and their coders will not need to learn ICD-10-PCS, they will need to learn ICD-10-CM. If the physician uses a superbill (a list of commonly used codes for that practice), it will need to be redesigned - and expanded - to include the ICD-10-CM codes. Some physician practices may find it tedious to continue to code using a superbill as it goes from a dual-sided to a multi-page document. Practices that do not currently use superbills and rely on coders to assign ICD-9-CM codes will need training in ICD-10-CM.
Hospitals, although only required to report ICD-10-PCS codes on inpatient claims, may choose to collect ICD-10-PCS data on all patients (including outpatients) in order to compare data internally. It is common practice currently for hospitals to collect ICD-9-CM procedure codes on all patient, even though they are "scrubbed" from the bill. As such, hospital coders will need to learn both ICD-10-CM and ICD-10-PCS. Of the two coding systems, ICD-10-PCS is expected to require more education as the structure is completely different from ICD-9-CM procedures. In addition, the clinical knowledge required to assign an ICD-10-PCS code is much greater than that needed to assign an ICD-9-CM code. I think coders with CPT coding experience will find the transition easier because of the level of detail needed to report those codes.
Right now AHIMA and the AAPC are training future ICD-10 trainers in preparation for training the masses. Software companies that utilize ICD-9-CM codes are currently applying the General Equivalency Mappings (GEMs) to map between ICD-9 and ICD-10 codes and beta testing the new code sets to ensure they work accurately. As an industry, experts aren't recommending that front line coders get trained prior to 2012, however, it is recommended that employers conduct a gap analysis to see what training their coders need and provide medical terminology, anatomy and physiology, and pathophysiology training starting now.
If you are a coding student, AHIMA recommends that your educational institution begin ICD-10 training in 2011 for associate and baccalaureate degree programs and in 2012 for coding certificate programs. If you plan to code prior to October 1, 2013, you will still need to learn ICD-9-CM coding and if you plan to graduate in 2012, it is likely you will learn both systems. For those considering enrolling in a coding program, determining the ICD-10 education schedule of the school will tell you a lot about the institution. Beware of the school with no plan.
The best part of the transition is that this is a great time for new coders to enter the field. This is a do-over, only it's the experienced coders doing to do-over and they will struggle with it just like new coders. It's going to be a level playing field for anyone interested in being a coder. So if you've ever considered it, now is the time!