“We weren’t looking at angry parents, we were looking at rude parents,” said Dr. Peter Bamberger, a study co-author and the associate dean for research at Coller School of Management at Tel Aviv University. The study used the kind of simulated crisis scenarios that are commonly performed to help medical staff practice, using actor “parents” and a realistic plastic baby “patient.” And the rude “mother” in the study said, loud enough for the staff to hear: “I knew we should have gone to a better hospital where they don’t practice Third World medicine.”

“It wasn’t anything horrible,” Dr. Bamberger said. “They weren’t going ballistic, they weren’t violent. They just said things that weren’t so pleasant for doctors to hear.”

But even such mild unpleasantness was enough to affect doctors’ and nurses’ medical skills. Individual performance and teamwork deteriorated to the point where diagnostic skills, procedural skills and team communication were impaired and medical errors were more likely, compared to control scenarios in which the mother would just say something general about being worried. The team’s ability to perform in critical medical situations with sick babies was affected for the rest of the day, the findings suggest.