P

Profile or battery consisting of many independent atomic observations (e.g. SMA12, electrolytes), usually done at one instrument on one specimen

F

Functional procedure that may consist of one or more interrelated measures (e.g. glucose tolerance test, creatinine clearance), usually done at different times and/or on different specimens

A

Atomic service/test/observation (test code or treatment code)

S

Superset--a set of batteries or procedures ordered under a single code unit but processed as separate batteries (e.g. routines = CBC, UA, electrolytes)

C

Single observation calculated via a rule or formula from other independent observations (e.g. Alveolar--arterial ratio, cardiac output)