This deluge of do-less recommendations results from research into tests and procedures that have been arguably overused. You'd think these pronouncements would bring a sea change in the way patients are treated in this country. But my guess is that little will change. Many doctors, maybe most, will ignore these findings and keep doing what they have been doing all along. Why? Healthcare critics are quick to point to the profit motive. And it's true that gastroenterologists, radiologists, urologists and physicians of all stripes make money from procedures that may not be necessary. But the real obstacle is not money. It's the culture of doctors, and that will be very hard to change.