In 1970, the (AMA) American Medical Association (AMA) implemented a five-digit code structure (00100-99607) for its Current Procedural Terminology (CPT). However, the codes are not meaningless, random numbers; each section and subsection of CPT are restricted to a subset of the codes, and “grouped” or related appropriately. The nuances of these groupings and special cases are described in this article.

The ampersand character (&) used in normal everyday grammar is shorthand for the word and or in Latin “et”.