Doctors, nurses and other health-care workers seldom challenge a colleague when they see mistakes being made in patient care, according to a new study.

Researchers spent more than 10,000 hours observing and interviewing more than 2,000 health workers at 19 hospitals around the country.

Among the stories they heard were of a nurse who gave up reminding a colleague to put up safety rails on a child's bed; a pharmacist who dispensed an inadequate prescription for pain medicine to a patient from a doctor who's a "jerk" and gives the pharmacy a hard time if challenged; and a nurse who watched a colon-surgery patient die after failing to convince a doctor who intimidated her that the man was in trouble.

None of the health workers or hospitals was identified by name.

The recent study was co-sponsored by the American Association of Critical-Care Nurses and VitalSmarts, a California firm that consults on leadership and organizational performance.

"People working in health centers see things every day that endanger patients, but only a small percentage of them talk with their colleagues about what they've seen," said Joseph Grenny, president of VitalSmarts. "What really surprised us was that not only are nurses reluctant to confront doctors and other nurses, but that doctors almost never speak up, even about problems with nurses."

Among the findings:

Eighty-four percent of physicians and 62 percent of nurses and other care providers have seen co-workers repeatedly taking shortcuts that could endanger patients;

Eighty-eight percent of physicians and 48 percent of nurses and other providers work with people who show poor clinical judgment, although the problems seem concentrated among a small percentage of colleagues -- about 10 percent;

Fewer than 10 percent of doctors, nurses and other caregivers said they directly confront colleagues about their concerns. And a fifth of the doctors said they've seen harm come to patients as a result of the behavior of those colleagues.

Overall, researchers found that health workers were reluctant to talk with colleagues about matters concerning competence, broken rules, mistakes, teamwork, lack of support, disrespect and micromanagement from doctors or supervisors.

Yet the minority of health-care workers who did raise concerns said it resulted in better patient care and made them more satisfied and committed to their jobs because of their candor.

One nurse administrator told researchers: "Finally, I told her 'if I ever see you tear the finger out of another glove, I will write you up for a willful violation.' Now she follows the rules." The administrator was describing how she handled a technician who repeatedly tore the tip off an index finger of her gloves while drawing blood from newborns that were supposed to be kept in the most sterile conditions possible.

Health workers gave various reasons for why they don't speak up -- such as a lack of confidence in their abilities, doubts that saying anything would do any good and fear of retaliation.

"This environment of poor communication and collaboration validates what our members have been telling us is the No. 1 barrier hindering optimal care for patients," said Kathy McCauley, president of the nurse's association.

"Everything that's been learned about reducing mistakes says that people must be able to share information freely. We must build environments that support and demand greater candor among staff if we are to make a demonstrable impact on patient safety."

The association also issued a new set of national standards aimed at promoting skilled communications among nurses and other caregivers.