“But the quality measures built into ObamaCare’s ACOs aren’t working so well yet either. Indeed, last week, virtually all of the health providers that Medicare has dubbed ‘Pioneer ACOs’—the program’s leaders and examples—sent a letter to Medicare officials overseeing the program in which they threatened to drop out. The reason is that the Pioneers feel that the performance and quality metrics aren’t up to snuff—and the data doesn’t yet exist to determine what the metrics should look like.”