Commas in a simple series
Use a comma to separate three or more items in a simple series, where none of the items contain internal commas. Do not use a comma to separate if the items are joined by and or or. Follow facility/employer specific guidelines for including a comma before the conjunction preceding the final item in the series.
Inclusion of the comma is recommended for clarity by the AMA, AHDI and the Gregg Reference Manual.
The patient comes in today with a chief complaint of nausea, vomiting, and diarrhea.
or
The patient comes in today with a chief complaint of nausea, vomiting and diarrhea.
or
The patient comes in today with a chief complaint of nausea and vomiting and diarrhea.
not
The patient comes in today with a chief complaint of nausea, and vomiting, and diarrhea.
Use parentheses instead of commas or dashes for clarity to set off a series that describes what precedes it.
The patient comes in today with multiple complaints (nausea, vomiting, and diarrhea), which she has had for 3 days.
not
The patient comes in today with multiple complaints - nausea, vomiting, and diarrhea - which she has had for 3 days.
not
The patient comes in today with multiple complaints, nausea, vomiting, and diarrhea, which she has had for 3 days.
Wiki