"A solid majority of physicians (64 percent) 'completely' agreed that they are obliged to report all significantly impaired or incompetent colleagues and, presumably, some number of those who did not agree completely would have agreed 'somewhat,'" he wrote.
DesRoches also notes some of the survey's limitations, including the effect nonresponders could have on the results.
"We did weight our results, but these adjustments are not perfect," she said.
She also acknowledged that evaluating incompetence is very subjective.
At least one other doctor agreed, saying that incompetence is not easy to judge.
"It's rare that you see a doctor who is completely incompetent," said Dr. Rick May, vice president for clinical consulting at HealthGrades, an independent group that rates health care practitioners and institutions. "What's more common is that you see a physician who's incompetent when it comes to using a certain medication or performing a certain procedure."
Doctors who do encounter these situations may take steps to address the problem, but will stop short of reporting a colleague. This, May said, could contribute to the researchers' findings about doctors failing to turn in other doctors.
"If I see a doctor who's incompetent with a drug or a procedure, I'm more likely to pull the colleague aside and talk to that person about using that drug or procedure," he said.
"They take their responsibilities to patients very seriously. When it comes to alcohol or drug abuse, they're going to make sure that doctor doesn't see patients and they'll take action immediately," he said.
While they're ethically obligated to report a physician with substance abuse problems, doctors also have a reponsibility to help others who need it.
"Physicians need to make sure we get help for our colleagues who may not be doing as well as they should. We want to maks sure people get treated and do the right thing," said Hood.
Despite the survey's flaws, experts agree that one finding is particularly sobering.
"A concerning aspect for me is that a significant proportion of doctors didn't really know how to go about addressing issues of incompetent of impaired physicians," said May.
"We are trying to get better processes in place in hospitals and large clinics, and we need to develop ways to help small practices as well," said Hood. "We also need to train our medical students and residents and expose them to the issue and educate them on the ways to handle it."
DesRoches also said that external regulation needs to be stronger and there should also be a confidential feedback mechanism so doctors know what happens when they do turn colleagues in.
"Right now, it goes off to to the state licensing board and doctors may never know what happens," she said.
It's also important for patients to realize they have the power to report an incompetent or impaired physician.
"If the doctor is in a hospital, they should go immediately to hospital administration and express their concerns," said May. "Outside the hospital, it might be appropriate to talk to a doctor's partners or talk to their primary physician and ask for advice, or go to the state medical board."