That's not to say that midsummer is the only time for potential problems. After all, some 100,000 Americans die from hospital medical errors each year — thousands every month. "But there is good evidence that errors are somewhat more common when residents first begin to work," notes Landrigan.
One study, published three years ago in the Journal of General Internal Medicine, reviewed 62 million death certificates issued between 1979 and 2006 and found that fatal medication errors consistently spiked in July by about 10 percent in U.S. counties with many teaching hospitals — and then subsided in August to levels on par with other months. Yet there was no measurable increase in counties with facilities that didn't employ residents, such as community hospitals.
"We were looking for all causes of death occurring in hospitals," explained study leader David P. Phillips of the University of California, San Diego, "and found no increase in death from surgical errors, hospital-acquired infection or other causes in any type of facility — only in fatal medication errors at teaching hospitals."
Another study, published in 2011 in the Annals of Internal Medicine, also suggests it's best to avoid teaching hospitals during July.
After reviewing data from 39 previous studies, it found death rates increased 4 to 12 percent — and patients endured longer hospital stays and more time in surgery — during July, when teaching hospitals "experience a massive exodus of highly experienced physician trainees" as rookies take their place, said study lead John Q. Young, M.D., of the University of California, San Francisco.
How to better avoid potential problems
1. Bring your own health records (including a Personal Medication Record). To reduce the risk of dangerous drug interactions, bring several copies of a list of everything you currently take — prescriptions as well as over-the-counter products, vitamins and herbal supplements — with their correct spelling, specific dosages and the reason for their use.
2. Ask a friend, relative or other health advocate to stay with you. Like you, advocates should also ask "why" when a drug or procedure is given. This will help ensure your day-to-day care is correct and provide an extra set of eyes and ears to understand the "big plan" of your treatment.
3. To lessen the chance of mix-ups, state your name to anyone providing you with care.
4. Know the name of the doctor who is ultimately in charge of your care. This lead provider should be (and usually is) an experienced primary attending physician — not a resident or intern — although that "primary" may change throughout your stay.
Sid Kirchheimer writes about health and consumer issues.
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