E/m coding standards and guidelines are based on the current procedural terminology codes and used to document the type and severity of patient conditions. While and are of course more semantically correct, there seem definite legitimate reasons to use the and tags for customer-written content. Explains the difference between 'rem' and 'em' units in css for font sizing and layout.

Check cms documentation guidelines, time-based coding, and get on the fast track to e/m level accuracy.