The only way I know is to compare to two real-time sources especially when others say they don't have any delays or its something that "occasionally" happens (the delay). Regardless, I've seen others say its real-time but in reality...not possible considering I know some institutions that pay a pretty penny to get the same news in real-time. I'm sure they would say something if they were paying hundreds or thousands per month while some Joe guy is getting the same thing too for a couple of bucks per month.