While the study underscored important differences among hospitals, the researchers also acknowledged that patients have little information about those differences. While consumers can use tools like Medicare’s Hospital Compare, which offers general quality information about individual hospitals, the data are very limited, Dr. Rosenberg said.

Many quality measures rely on reporting about whether the hospital gives patients an antibiotic, not whether they develop an infection, and they do not distinguish among different diseases. A hospital that is a top performer in heart surgery, for example, may be a poor place to choose to get a knee replacement.

The authors say patients need such information. “This paper raises the question of why don’t we have broader outcomes measurement and transparency around performance,” said Dr. Justin B. Dimick, one of the authors and a surgeon and researcher at the University of Michigan.

The researchers argue that this kind of information is necessary to judge the quality of the narrow network of hospitals increasingly offered by insurance companies. “The key thing about narrow networks is that they are created based on costs, negotiated prices and things like that,” Dr. Dimick said. “You need to pay attention to both cost and quality.”

Hospitals that excel in heart surgery or knee replacements should be rewarded by having more patients come and potentially being paid more for their care, Dr. Rosenberg said. “It’s an opportunity to improve health that has been underleveraged and underappreciated,” he said.

But researchers say obtaining information about outcomes is becoming increasingly difficult. Federal and state databases release less information than they used to.

If the incoming Trump administration wants to make health care function more like a market where people are encouraged to shop for medical care on their own, the researchers say, people will need that information.