Having worked within a large system that is moving toward becoming an ACO, I can echo Indy's and Michael's posts.
Of course they want 1 system. It is the corporate philosophy. Buy 1 brand of computers even if it costs more for uniformity. Have 1 EMR because we have 1 standard even if it is not user friendly and may not do everything we want but is moving in the right direction, maybe it will get there.
Our system theoretically had a lab link to AC 2 years ago. They have yet to turn it on. They are Beta testing it, they changed vendors for their outside links and started all over, they are re Beta testing it. Their reps have no knowledge of when this will procede. Of course, if I used their EMR... (eClinicalworks)
They have a number of physicians on AC. I actually know one who was beta testing it (interesting he is since I asked about a lab link before he had AC, but that's OK, he is diligent) and was told it works well. But still, they have not released it.
I have treatened to leave their labs. Quest has a AC interface. They finally gave me a discount for cash patients I had been requesting for a long time, iff I stuck with them. Games, Games, Games.
They have stated they will have linkages for outside EMRs but with that track record, why should I expect any difference.
