I recently passed my CPC exam and during studying I was prompted to question my understanding of the use 7th character "A"-Initial Encounter. When ICD10-CM was introduced, we were taught that "A" was used at the initial patient encounter, then "D"-in most cases-was appropriate for subsequent visits. However, the definition reads "....Examples of active treatment are: surgical treatment, emergency department encounter, and evaluation and continuing treatment by the same physician or a different physician." According to this definition, it would be appropriate to code using the "A" as the 7th character for services beyond the initial encounter as long as that patient is receiving active treatment. I may be overthinking this (as I sometimes do), but just wanted to be sure I am clear on this as I do code for injuries and subsequent care frequently. Any clarification would be appreciated.