english: To do reliable research on any condition, scientists must agree on the specific characteristics that make up that condition so they're all talking about the same thing, and with PMS, this has not been the case.
non_english: Výskum akejkoľvek zdravotnej potiaže vyžaduje vedeckú zhodu na špecifických prejavoch danej potiaže, aby sa zaručilo, že všetci hovoria o tom istom, a toto pre PMS neplatilo.