Correspondence
Post-Call Accidents
N Engl J Med 2005; 352:1491-1492April 7, 2005
- Article
To the Editor:
I participated in the study reported by Barger and colleagues (Jan. 13 issue),1 and my comments might inform interpretations of the results by nonparticipants. The 2737 interns who responded represented only 15 percent of the 18,447 interns invited to participate. Thus, there is a great risk of nonresponse bias.2 That the demographic characteristics of the participants reflected those of all the interns reduces this risk only if the demographic characteristics explain most of the variance in the responses of potential participants. This seems unlikely. It is more likely that interns interested in the relations among sleep, medical errors, and motor vehicle accidents were more likely to participate and to report certain behavior patterns than were other interns. These “interested” interns also might be likely to decipher the study's hypothesis, as I did, and this may have influenced responses.
Common sense suggests that sleeplessness has some relation to errors (both behind the wheel and on the wards). However, just as common sense will sometimes prove wrong when put to the test, epidemiologic studies conducted by researchers invested in the results suffer from similar imperfections.3
3 ReferencesScott D. Halpern, M.D., Ph.D.
Hospital of the University of Pennsylvania, Philadelphia, PA 19104
shalpern@mail.med. upenn. edu 1
Barger LK ,Cade BE ,Ayas NT , et al. Extended work shifts and the risk of motor vehicle crashes among interns. N Engl J Med 2005;352:125-134
Full Text | Web of Science | Medline2
Halpern SD ,Asch DA . Improving response rates to mailed surveys: what do we learn from randomized controlled trials? Int J Epidemiol 2003;32:637-638
CrossRef | Web of Science | Medline3
Rothman KJ . Conflict of interest: the new McCarthyism in science. JAMA 1993;269:2782-2784
CrossRef | Web of Science | Medline
To the Editor:
As internal medicine residents, we have often wondered what effect the long hours of training have on our own health and safety. The study by Barger et al. clearly shows that even within the confines of work-hour requirements, residents remain at risk for motor vehicle accidents. The University of Chicago has had some success in solving the problem of resident fatigue and motor vehicle crashes. Several years ago, after a series of car accidents involving post-call residents, the internal medicine residency program established the Safe Ride Fund through the donation of a former resident. Over the past 18 months, this service has been used more than 13 times per month by the housestaff. With the post-call option to take a free taxicab home from the hospital and back to work the next day, we have not had a single reported motor vehicle accident involving a post-call resident. Although doctors clearly make sacrifices for their profession, their own health and safety need not be one of them.
William Borden, M.D.
Ryan Kamp, M.D.
University of Chicago Hospitals, Chicago, IL 60637
wborden@medicine.bsd. uchicago. edu To the Editor:
As a resident myself, I was very curious to read the article on the extended hours of interns and their relation to motor vehicle accidents. Anecdotally, I know of two residents who — both during their intern year — were involved in motor vehicle accidents immediately after having worked an extended shift. In the final analysis of how to remedy this situation, I find it shocking that one of the proposals mentioned in the article is to supply taxicab vouchers to residents after extended shifts. If these interns and residents are exhausted enough to have an accident while driving, what does this say about their ability to make life-saving (or life-threatening) decisions with their patients? This is the real issue that must be addressed.
Kristin E. Hunt, M.D.
University of New Mexico, Albuquerque, NM 87114
kehunt@salud.unm. edu To the Editor:
The article by Barger et al. concerning extended work hours and motor vehicle crashes is congruent with many reports citing the hazards of sleep deprivation for physicians in training. Barger and colleagues found that a sleepy house officer is twice as likely to have a crash, and it may occur while the house officer is commuting. Almost hidden in the discussion is the allusion to former times when “resident physicians . . . lived, worked, and slept in the hospital in order to follow the evolution of the illnesses.” Those physicians were often without cars and dependent on the hospital for room and board and frequently had deferred starting a family; many were our great teachers and clinicians.
One might argue that the former monastic, undistracted, self-effacing training lifestyle had some valuable elements that should be preserved to help generate our future leaders and reduce the risk of injury from a motor vehicle crash.
Robert C. Wallach, M.D.
New York University Clinical Cancer Center, New York, NY 10016
wallachrc@mindspring.com Author/Editor Response
Although it may be true that participants in our study were not representative of all interns with respect to their interest in or knowledge of the study hypotheses, that would not explain why the interns who participated with Dr. Halpern in our study had more than twice as many motor vehicle crashes after extended shifts (≥24 hours) as after nonextended shifts (<24 hours) when they were compared with themselves. In addition, we designed the study to guard specifically against this type of bias by also gathering data on work hours prospectively, well before data on documented motor vehicle crashes were collected. The monthly rate of motor vehicle crashes increased by 9.1 percent for every extended work shift scheduled per month (i.e., 91 percent on an every-third-night schedule). We think it unlikely that the presumed interests of the participants or the investigators in the outcomes of this research could account for the concordant results from these two different analytic techniques.
Dr. Wallach correctly points out that forcing trainees to live in the hospital where they work would eliminate commuting and thereby reduce their risk of motor vehicle crashes. Not even this draconian policy could bring back the era in which trainees had the opportunity to sleep in the hospital. Our data indicate that the current health care environment of high acuity and often intensive care with shortened lengths of stay would prevent trainees from obtaining the sleep they need even if they were truly “resident” in the hospital.
Although the voluntary taxicab voucher program, described by Drs. Borden and Kamp, may reduce the risk of crashes, the limited reported use of taxicab vouchers supports our concern that the residents' judgment of their impairment is compromised by chronic sleep deprivation.1 Moreover, as Dr. Hunt points out, taxicab vouchers do not address the risks that extended work shifts pose for patients. Our group has recently shown that interns in critical care units have twice as many attentional failures2 and make 36 percent more serious medical errors3 — including 5.6 times as many diagnostic errors — when scheduled to work extended work shifts as compared with shifts of up to 16 hours. Taken together, these three studies indicate that the health and safety of interns and their patients would benefit from the elimination of the marathon, 30-consecutive-hour work shifts that the Accreditation Council for Graduate Medical Education continues to sanction.4
4 ReferencesLaura K. Barger, Ph.D.
Brigham and Women's Hospital, Boston, MA 02115Najib Ayas, M.D., M.P.H.
University of British Columbia, Vancouver, BC VSZ 3J5, CanadaCharles A. Czeisler, Ph.D., M.D.
Brigham and Women's Hospital, Boston, MA 02115
caczeisler@hms.harvard. edu for the Harvard Work Hours, Health, and Safety Group
1
Van Dongen HP ,Maislin G ,Mullington JM ,Dinges DF . The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep 2003;26:117-126[Erratum, Sleep 2004;27:600.]
Web of Science | Medline2
Lockley SW ,Cronin JW ,Evans EE , et al. Effect of reducing interns' weekly work hours on sleep and attentional failures. N Engl J Med 2004;351:1829-1837
Full Text | Web of Science | Medline3
Landrigan CP ,Rothschild JM ,Cronin JW , et al. Effect of reducing interns' work hours on serious medical errors in intensive care units. N Engl J Med 2004;351:1838-1848
Full Text | Web of Science | Medline4
Accreditation Council for Graduate Medical Education. Common program requirements. Chicago: Accreditation Council for Graduate Medical Education, 2005. (Accessed March 17, 2005, at http://www.acgme.org/acwebsite/dutyhours/dh_dutyhourscommonpr.pdf.)
