The manual
I've had this happen to me, I had an "IAS disagree" message show up on my PFD right after I made the "80 knots" call out. I was flying a brand new 737 NG, by brand new I mean an NG with probably 3 or 4 months of continuous airline use.
Our manual says that past 80 knots we only reject a take off for Engine failure, fire, unsafe/unable to fly. And as the previous pilot mentioned you fly specific pitch and power settings, and continuously monitor your standby instrument.
Eventually the message disappeared, only to come back during approach phase. Upon touchdown both EEC's went to alternate mode. The plane was written up, we told maintenance and we where given another plane for the flight to another city. End of story.