Before revision: When information on more than three patients is included, the case series is considered to be a systematic investigation designed to contribute to generalizable knowledge (i.e., research), and therefore submission is required to the IRB .
After revision: When information on more than three patients is included, the case series is considered to be a systematic investigation designed to contribute to generalizable knowledge (i.e., research), and therefore submission is required to an institutional review board (IRB) .