Here's a story where AIr Traffic Control (ATC) cleared a pilot to a safe altitude. The pilot read back an incorrect (potentially unsafe) altitude -- and, ATC failed to notice. It turned out ok.
What can EMS learn?
You can readily see some parallels. Multitasking, high stress, life and death, vital communications...
And, maybe you think you know what order Online Medical Control is giving you but you're actually given a different order. But, the communications kinda' faded or you had two people in your other ear. Instead of asking for them to say again, you read back what you thought you heard. And, because of their own case of two people in their other ear, you get a reflexive "read-back correct".
So, pay attention. Focus and listen. If you are not sure you heard correctly, take the initiative.