post or quote anything claiming to be factual without giving sources, or at the very least laying out a logical argument to back it up. This particularly goes for anything containing figures, including percentages.
Thou shalt stand by your data, or shut up.
(Oh, and some sources are more valid than others, but that’s another point. Rule of thumb: if the ‘institution’ has the word ‘truth’ in the title, probably safe to ignore it.)
Seriously, I’m running out of synonyms for ‘vacuous’.