Stress and depression often cause young physicians to struggle in their residencies, leaving them with poor clinical judgment and inadequate medical knowledge.
The finding, published in today's Journal of the American Medical Association, comes from a nationwide survey of 298 directors of internal medicine residency programs.
The study found diverse and complex issues facing the programs in dealing with "problem residents," rookie doctors with problems significant enough that supervisors need to intervene.
According to the program directors, about 7 percent of their residents are in this category. But little is known about contributing factors and how best to manage the problem residents.
That's why physicians at the Johns Hopkins School of Medicine conducted the study.
About a third of the program directors believed that residents older than 35, foreign medical school graduates and members of an underrepresented minority had an increased chance of being identified as a problem resident.
The study's authors suggested that cultural and language differences, expectations and previous experiences might put these groups at a disadvantage at the beginning of their training.
Discrimination could also be a factor, the study noted.
But for all of the doctors, residency is a demanding time that brings situational, personal and professional stresses.
These newly minted medical school graduates have often moved to new cities to begin their residencies. For the first time, they have responsibility for patients. They are learning to negotiate the complicated system in a hospital - and they're working about 80 hours a week.
"It's not surprising, given the demands both personally and professionally, that many residents have problems," said Dr. Scott M. Wright, one of the study's authors and co-director of the medical education fellowship at Johns Hopkins Bayview Medical Center.
Chief residents and attending physicians were the most likely ones to identify problem residents, by watching them in action, through chart reviews or a critical incident, or through a poor performance at a morning report.
The most helpful interventions, according to the program directors, were frequent feedback sessions and an assigned mentor.
The study's authors believe residency programs need to be more aggressive about identifying these residents and working with them. About 57 percent of the problem doctors finish their residencies.
At the University of Maryland Medical Center, internal medicine residents receive written evaluations every month. A few might need extra tutoring, or counseling in becoming more efficient, or advice on what they need to be reading.
"We try and keep that loop very tight so things don't slip through," said Dr. Susan D. Wolfsthal, the residency program director for the Department of Medicine at Maryland.
"I talk to people all the time ... but it doesn' t mean they're not good doctors."