7 Things You Need to Know About GEMs (General Equivalence Mappings)

Health Information Services ICD-10

ID 100133158 General Equivalence Mappings or GEM as it is popularly called comes into use if you are looking to translate lists of codes, coded data or code tables while converting a system or any other application containing ICD-9-CM.  GEM is developed as an essential tool to assist conversions of ICD-9-CM (International Classification of Diseases, 9th Edition, Clinical Modification) to ICD-10 (International Classification of Diseases, 10th Edition) and vice-versa.

In other words, GEM is the forward and backward mapping system amongst ICD-9-CM and ICD-10 coding, which is also referred to as a ‘crosswalk’.  Healthcare Information Services (HIS) will simply help to make this transition smooth and easy for your organization.

Who is GEM intended for?

GEM is intended for coding professionals, providers, informatics professionals, payers, medical researchers and individuals who need to use coded data. It can be used in various conversations of payment systems, coverage edits and payments, risk-adjustment logic, research application and quality measures. Trained professionals at Healthcare Information Services (HIS) will ensure that your relevant data is integrated thus making your job easy and your practice efficient!

Checkout these 7 things that you must know about GEM:

  1. It is pointed out in GEM that there are resemblances between ICD-9-CM code and ICD-10-CM or ICD-10-PCS (Procedure Coding System). For example, to understand the complete meaning of ICD-9-CM, all reasonable translation alternatives must be involved, which includes index entries, tabular instructions, applicable coding clinic advice and guidelines.
  2. There may be instances of no translation between ICD-9-CM and ICD-10 codes. In fact, when there is no credible translation between them, there is a ‘No Map’ flag indication. For example, procedure code 89.8 in ICD-9-CM- Autopsy has no equitable translation in ICD-10-PCS.
  3. GEM is designed to work both ways- that is from ICD-9-CM to ICD-10 and back as a bi-directional translation dictionary. This will help find a code in both coding systems according to the structure and concepts, though one is not a mirror-image of the other. You can look reverse and use backward mapping to convert coverage decision or payment logic between the codes.
  4. GEM is designed to be used by all- payers and providers as a general purpose translation tool using coded data. Translations of coded data are based on meaning- as contained in index entries, tabular instruction, and any applicable coding clinic advice. In fact, these were developed independently without any reference to the Medicare data- thus can be used by all.  
  5. GEM validation is also being currently done as a part of the conversation process from ICD-9 CM to ICD-10 based on Medicare Severity Diagnosis Related Groups (MS-DRG). The process of conversion of MS-DRG starts with preliminary translation that uses ICD-10 to ICD-9-CM GEMs and then ICD-9-CM to ICD-10 GEMs to recognize any issues related to conversion. At present, all 4 GEMs are being verified and discrepancies noted to make necessary changes.
  6. The main aim of ICD-10 MS-DRG coding and conversion is to reproduce MS-DRG logic. This means that the method of replicating ICD-9-CM with those of ICD-10 is somewhat automated in GEM. This is because, a record coded in ICD-10-CM/PCS and managed according to the changed ICD-10-based MS-DRG, will be given to the same MS-DRG, as the similar record coded in ICD-9-CM and processed according to the present MS-DRG logic.
  7. GEM will act as a ‘translation dictionary’ between the two sets of codes and will help in successful transition to ICD-10. However, it is not a substitute for coding.

Healthcare Information Services (HIS) remains your foremost choice that will help you with a smooth transition and better understanding of General Equivalence Mappings (GEM).