Wiki ICD-10-CM Guidelines/Conventions

these are not official symbols they would be specific to a particular publisher. Each publishers has unique symbols to indicate things like the need for a 6th or 7th character. Whoever wrote this article that you have referenced knows how to confused people for sure. whatever book you decide to use you need to read in the front of the book what the different notations mean for that book. the official guidelines for ICD-10CM are not CMS guidelines they are CDC and WHO created guidelines.
 
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