Question

I need help explaining three important points about the format of the ICD coding manual. What are GEMs and the two GEMS files?

Answer 1

ICD-10 CM is a international classification of disease-10-clinical modificaiton.
It has 3-7 characters and character 1 is alpha includes all letters except is character 2 is numeric, 3 to 7 is alpha or numeric, Dummy place holder indicates X. It codes extend longer than 3 characters have decimal points after the first 3 characters.
7th character used for some subjects like musculoskeletal, injury, obstetrics, external cause of injury. It has a tabular list and index. The alphabetic index is the main term in alphabetical order with subterm under the main term, index divided into two parts, disease and injuries, and external causes.
GEMs are general equivalence mappings, it is the more complex translation between ICD-10-cm and ICD-9-cm. It is a tool can be used to convert data from ICD-9 to ICD-10-cm and PCS. It is referred to as forwarding mapping. one GEM file for mapping ICD-9-cm to ICD-10-cm one more file is for ICD-10-cm to ICD-9-cm.