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Cited by 913Sleep and Work-Related FatigueHospital Admissions and OutcomesHealthcare professionals’ stress and burnout

Effect of Reducing Interns' Weekly Work Hours on Sleep and Attentional Failures

Open access
Lockley, Steven W., Cronin, John W., Evans, Erin E., Cade, Brian E., Lee, Clark J., Landrigan, Christopher P., Rothschild, Jeffrey M., Katz, Joel T. +4 more·2004·New England Journal of Medicine
DOI 10.1056/nejmoa041404
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Abstract

Background Knowledge of the physiological effects of extended (24 hours or more) work shifts in postgraduate medical training is limited. We aimed to quantify work hours, sleep, and attentional failures among first-year residents (postgraduate year 1) during a traditional rotation schedule that included extended work shifts and during an intervention schedule that limited scheduled work hours to 16 or fewer consecutive hours. Methods Twenty interns were studied during two three-week rotations in intensive care units, each during both the traditional and the intervention schedule. Subjects completed daily sleep logs that were validated with regular weekly episodes (72 to 96 hours) of continuous polysomnography (r=0.94) and work logs that were validated by means of direct observation by study staff (r=0.98). Results Seventeen of 20 interns worked more than 80 hours per week during the traditional schedule (mean, 84.9; range, 74.2 to 92.1). All interns worked less than 80 hours per week during the intervention schedule (mean, 65.4; range, 57.6 to 76.3). On average, interns worked 19.5 hours per week less (P Conclusions Eliminating interns' extended work shifts in an intensive care unit significantly increased sleep and decreased attentional failures during night work hours.

Integrity signals

Registry

Crossref · 10.1056/nejmoa041404

Cites

44 of 44 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

1 of 25 cited sources checked · 0 supported · 0 flagged · accuracy not yet measured

  • Interpretationcitation

    The increased incidence of attentional failures during night work among interns during the traditional as compared with the intervention schedule may impede their ability to care for patients and their education.

    “The increased incidence of attentional failures during night work among interns during the traditional as compared with the intervention schedule may impede their ability to care for patients and their education.27 , 37”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [27] source

      The Results and Discussion passages (page not provided) concern sleep-dependent motor-skill learning, not interns’ night work. Searches for attentional failures, traditional versus intervention schedules, patient care, and interns’ education found no passage addressing the claim. (LLM, conf=0.75)

      Experimental — accuracy not yet measured
    • cites [37] source
  • Findingown data

    The traditional schedule had three times as many shifts that were prefaced by fewer than 2 hours of sleep in the preceding 24 hours as did the intervention schedule.

    “The traditional schedule had three times as many shifts that were prefaced by fewer than 2 hours of sleep in the preceding 24 hours and more than twice as many attentional failures during night work as did the intervention schedule.”
    Quote in the paperSubstantial claim
  • Findingreasoning

    During both the traditional and the intervention schedule, reported work hours often exceeded both the scheduled weekly hours and the number of consecutive work hours scheduled, owing to the interns' obligation to ensure the continued care of their patients after their own shift was over.

    “Furthermore, during both the traditional and the intervention schedule, reported work hours often exceeded both the scheduled weekly hours and the number of consecutive work hours scheduled, owing to the interns' obligation to ensure the continued care of their patients after their own shift was over.”
    Quote in the paperSubstantial claim
  • Findingown data

    Attentional failures occurred at 1.5 times the rate during the day (7 a.m. to 10 p.m.) on the traditional schedule as compared with the intervention schedule (P=0.07).

    “and 1.5 times the rate during the day (7 a.m. to 10 p.m.) (P=0.07).”
    • Also stated in: § attentional failures · hedged
      “a trend (P=0.07)toward a reduction in attentional failures during day and evening call (7 a.m. to 10 p.m.) was also apparent”
    Quote in the paperNot a substantial claim
  • Findingown data

    Interns slept more in the 24 hours preceding each working hour on the intervention schedule than on the traditional schedule (P<0.001).

    “slept more in the 24 hours preceding each working hour (P<0.001)”
    Quote in the paperSubstantial claim
  • May combine two claims. 17
  • Classified as probably not a substantial claim. 7

  • May combine two claims.

    Findingown data

    During the traditional schedule, 31 percent of work hours were preceded by 4 or fewer hours of sleep in the preceding 24 hours and 19 percent by 2 or fewer hours, as compared with 13 percent and 6 percent, respectively, during the intervention schedule (P<0.001 for both comparisons).

    “During the traditional schedule, 31 percent of work hours were preceded by 4 or fewer hours of sleep in the preceding 24 hours and 19 percent of work hours were preceded by 2 or fewer hours of sleep in the previous 24 hours, as compared with 13 percent and 6 percent, respectively, during the intervention schedule (P<0.001 for both comparisons)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    On average, interns slept for 1.76±1.04 hours between 9 p.m. and 8 a.m. during the traditional schedule, significantly longer than they slept while working the corresponding hours during the intervention schedule (1.29±0.90 hours per shift, P=0.02).

    “On average, interns slept for 1.76±1.04hours between 9 p.m. and 8 a.m. during the traditional schedule, significantly longer than they slept while working the corresponding hours during the intervention schedule (1.29±0.90hours per shift, P=0.02).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The weekly durations of sleep and work were significantly inversely correlated (r=-0.57, P<0.001), with a predicted loss of 19.2 minutes of sleep per week for each additional hour of work per week.

    “The weekly durations of sleep and work were significantly inversely correlated (r=¡0.57,P<0.001), with a predicted loss of 19.2 minutes of sleep per week for each additional hour of work per week (Fig. 3C).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The intervention schedule had no extended work shifts, and 96 percent of work hours occurred within the 16 hours scheduled, in contrast to the traditional schedule, in which only 58 percent of work hours occurred within the first 16 hours on duty.

    “The intervention schedule had no extended work shifts (Fig. 4B), and 96 percent of work hours occurred within the 16 hours scheduled, in contrast to the traditional schedule, in which only 58 percent of work hours occurred within the first 16 hours on duty.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    During the traditional rotation, over half of work shifts (133 of 223, or 60 percent) were extended (more than 24 hours) and 84 percent of work hours occurred during these shifts.

    “During the traditional rotation, over half of work shifts (133 of 223, or 60 percent) were extended (more than 24 hours) and 84 percent of work hours (4255 of 5036) occurred during these shifts”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The ACGME has recently limited work hours for U.S. medical residents to less than 320 hours in a four-week period, with up to 32 additional hours for programs granted exceptions.

    “he accreditation council for Graduate Medical Education (ACGME) has recently limited work hours for U.S. medical residents to less than 320 hours in a four-week period, with up to 32 additional hours for programs granted exceptions. 1”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1] Common program requirements (resident duty hours). Chicago: Accreditation Council for Graduate Medical Education, February 2003. (Accessed October 4, 2004, at http://www.acgme.org/DutyHours/dutyHoursCommonPR.pdf.)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Study design and conductnone given

    Caffeine use, compliance with the protocol, and individual differences in the need for sleep among subjects could not be controlled in this field study.

    “considering the fact that caffeine use, compliance with the protocol, and individual differences in the need for sleep among subjects could not be controlled in this field study.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Our findings may apply not only to residents working in critical care units but also to those on other rotations and specialties and to more senior residents, attending physicians, nurses, and others.

    “Our findings may apply not only to residents working in critical care units but also to those on other rotations and specialties and to more senior residents, attending physicians, nurses, and others.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Interns took prophylactic naps before two thirds of the overnight shifts during the intervention schedule, thereby preemptively attenuating the deleterious effects on alertness and neurobehavioral performance of continuous wakefulness and blunting the circadian performance nadir.

    “It is noteworthy that interns took prophylactic naps before two thirds of the overnight shifts during the intervention schedule, thereby preemptively attenuating the deleterious effects on alertness and neurobehavioral performance of continuous wakefulness and blunting the circadian performance nadir.38”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [38] Jewett ME. Models of circadian and homeostatic regulation of human performance and alertness. (Ph.D. thesis. Cambridge, Mass.: Harvard University, 1997.)

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationreasoning

    This sizable and unidentified proportion of the population may be particularly vulnerable to the effects of extended work shifts and chronic sleep restriction imposed during residency training, possibly unwittingly placing themselves and their patients at markedly increased risk for fatigue-related errors.

    “This sizable and unidentified proportion of the population may be particularly vulnerable to the effects of extended work shifts and chronic sleep restriction imposed during residency training, possibly unwittingly placing themselves and their patients at markedly increased risk for fatigue-related errors.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Slow eye movements are correlated with performance failures on the psychomotor vigilance task and are reduced by treatments that counteract fatigue and thus improve neurobehavioral performance.

    “Slow eye movements are correlated with performance failures on the psychomotor vigilance task 21 and are reduced by treatments that counteract fatigue and thus improve neurobehavioral performance.[34][35][36]”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [21] Cajochen C, 1999, Am J Physiol source
    • cites [34] source
    • cites [35] Phipps-Nelson J, 2003, Sleep source

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductown data

    The number of slow eye movements was determined by a single scorer in an unblinded fashion and validated in a blinded fashion by an independent scorer (r=0.94, P<0.001).

    “The number of slow eye movements recorded during all waking polysomnographic epochs was determined by a single scorer according to established criteria in an unblinded fashion.21 Results were then validated in a blinded fashion by an independent scorer who compared them with the rates recorded from 9 p.m. to 3 p.m. in a subgroup (10 percent) of EOG recordings (r=0.94,P<0.001).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [21] Cajochen C, 1999, Am J Physiol source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationown data

    Our data on actual work hours reveal that the maximal number of scheduled work hours must be much lower to allow for this inevitability.

    “Our data on actual work hours reveal that the max-imal number of scheduled work hours must be much lower to allow for this inevitability.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data

    The study used a within-subjects design comparing the same 20 interns during traditional and intervention schedules in MICU and CCU.

    “Using a within-subjects design, we studied 20 interns during two three-week rotations in the medical intensive care unit (MICU) and coronary care unit (CCU) while they followed a traditional schedule with extended work shifts of 30 consecutive hours scheduled every other shift and an intervention schedule in which work shifts were a maximum of 16 consecutive hours scheduled.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The presence of slow-rolling eye movements during wakefulness is indicative of profound fatigue in both occupational settings and laboratory settings and parallels subjective sleepiness, theta activity on electroencephalography, and impaired neurobehavioral performance.

    “The presence of slowrolling eye movements during wakefulness is indicative of profound fatigue in both occupational settings 29 and laboratory settings 21 and parallels subjective sleepiness, theta activity on electroencephalography, and impaired neurobehavioral performance 21,29”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [29] source
    • cites [21] Cajochen C, 1999, Am J Physiol source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    It is unlikely that simply decreasing the number of hours worked in a week without incorporating the underlying principles of sleep physiology would yield a similar increase in sleep or reduction in attentional failures.

    “we believe it unlikely that simply decreasing the number of hours worked in a week without incorporating the underlying principles of sleep physiology would yield a similar increase in sleep or reduction in attentional”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data

    Our study provides objectively validated data on work hours, sleep, and attentional failures among medical trainees in situ and quantifies the effects of eliminating extended work shifts on these measures.

    “Our study provides objectively validated data on work hours, sleep, and attentional failures among medical trainees in situ and quantifies the effects of eliminating extended work shifts on these measures.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    Eliminating interns' extended work shifts in an intensive care unit significantly increased sleep and decreased attentional failures during night work hours.

    “Eliminating interns' extended work shifts in an intensive care unit significantly increased sleep and decreased attentional failures during night work hours.”
    • Also stated in: § attentional failures · plain
      “The elimination of extended work shifts had a significant effect on the number of hours worked by interns, the duration of sleep, and the rate of attentional failures.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    Since nearly a third of their work hours (31 percent) were preceded by 6 or fewer hours of sleep in the preceding 24 hours, they continued to carry a substantial sleep debt, accounting for the high residual rate of attentional failures on both schedules, even during the day.

    “Since nearly a third of their work hours (31 percent) were thus preceded by 6 or fewer hours of sleep in the preceding 24 hours, they continued to carry a substantial sleep debt, accounting for the high residual rate of attentional failures on both schedules, even during the day.22”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [22] source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Subjective reports indicated that, before the new regulations were implemented, some trainees worked up to 140 hours per week, although the validity of such reports has been questioned.

    “Subjective reports indicated that, before the new regulations were implemented, some trainees worked up to 140 hours per week, [12][13][14][15][16] although the validity of such reports has been questioned.3,17”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [12] source
    • cites [13] Baldwin DC, 2004, Sleep source
    • cites [14] Czeisler CA, 2004, Sleep

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

20 of 20

  • The paper relies on this without support.

    Knowledge of the physiological effects of extended (24 hours or more) work shifts in postgraduate medical training is limited.

    “Knowledge of the physiological effects of extended (24 hours or more) work shifts in postgraduate medical training is limited.”
1 of 1

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • A randomised controlled trial found that limiting first-year resident physicians to 16 consecutive work hours significantly improved resident alertness and patient safety.

    “A randomised controlled trial found that limiting first-year resident physicians to 16 consecutive work hours significantly improved resident alertness and patient safety.”

    From National improvements in resident physician-reported patient safety after limiting first-year resident physicians’ extended duration work shifts: a pooled analysis of prospective cohort studies (2023) · cites this paper as [7]

    The coverage schedules section describes a within-subjects comparison of traditional shifts with shifts scheduled for no more than 16 consecutive hours. The attentional failures section reports significantly fewer overnight attentional failures on the intervention schedule (P=0.02), supporting improved alertness. This paper does not report a measured improvement in patient safety; it says patient-safety effects need further study and identifies a separate article on medical errors. The cited passages also do not establish that interns were randomized. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Sleep diaries were based on ones previously validated against polysomnography in resident physicians and used in shift-workers.

    “Diaries were based on ones previously validated against the gold-standard for sleep assessment (polysomnography) in resident physicians55 and used in shift-workers56.”

    From Irregular sleep/wake patterns are associated with poorer academic performance and delayed circadian and sleep/wake timing (2017) · cites this paper as [55]

  • Young children, being unmarried, working long hours, overweight and obesity, and measures of poor health including acute and chronic respiratory conditions, pain, and anxiety increase the odds of short sleep and have a null or inverse association with long sleep.

    “Young children, being unmarried (19,26), working long hours (11,27,28), overweight and obesity (3-5), and measures of poor health (13,14,16,20,37,38,40) including acute and chronic respiratory conditions, pain, and anxiety increase the odds of short sleep and have a null or inverse association with long sleep.”

    From Sleep Duration in the United States: A Cross-sectional Population-based Study (2009) · cites this paper as [11]

Cites

Flagged first, then by citations

Research works printed but not linked: 7

  1. Mullins MD, 2003, N Engl J Med, 348, 665
  2. Czeisler CA, 2004, Sleep, 27, 371
  3. 10.1097/00000658-200304000-00001 · DOI
  4. Richardson GS, 1996, Sleep, 19, 718
  5. Cajochen C, 1999, Am J Physiol, 277, R640
  6. Jewett ME. Models of circadian and homeostatic regulation of human performance and alertness. (Ph.D. thesis. Cambridge, Mass.: Harvard University, 1997.)
  7. Van Dongen HPA, 2004, Sleep, 27, 423

Cited by

Sorted by citations

Related

Authors
Lockley, S. W., Cronin, J. W., Evans, E. E., Cade, B. E., Lee, C. J., Landrigan, C. P., Rothschild, J. M., Katz, J. T., Lilly, C. M., Stone, P. H., Aeschbach, D., & Czeisler, C. A.
Affiliations
Brigham and Women's Hospital (US)
ORCID
Venue
New England Journal of Medicine
Publisher
Massachusetts Medical Society
Published
2004-10-28
Volume
351
Issue
18
Pages
1829-1837
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
DOI
10.1056/nejmoa041404
OpenAlex
W2166406376
Cited by
913
References
41
Citations by year
2026: 20 · 2025: 32 · 2024: 24 · 2023: 24 · 2022: 26 · 2021: 31 · 2020: 19 · 2019: 46 · 2018: 36 · 2017: 33 · 2016: 37 · 2015: 41 · 2014: 57 · 2013: 49 · 2012: 54
FWCI
87.88
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • Surrey Research Insight Open Access (The University of Surrey) (submittedVersion)
Funders
  • National Aeronautics and Space Administration (NCC958)
  • Brigham and Women's Hospital (M01 RR02635, T32 HL079010)
  • National Space Biomedical Research Institute (NCC 9‐58)
  • Wellcome Trust
  • Agency for Healthcare Research and Quality (F32 HS14130, K08 HS13333, R01 HS 12032, RO1 HS12032)
  • National Heart, Lung, and Blood Institute (T32 HL079010)
  • National Center for Research Resources (M01RR002635)
  • National Institute for Occupational Safety and Health (R01 OH07567)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
  • Health Sciences › Medicine › Emergency Medicine › Hospital Admissions and Outcomes
  • Health Sciences › Health Professions › General Health Professions › Healthcare professionals’ stress and burnout
Keywords
sleep duration, attentional failures, graduate medical education, intensive care unit, sleep deprivation, resident fatigue
MeSH terms
Adult, Attention, Female, Humans, Intensive Care Units, Internal Medicine, Internship and Residency, Male, Personnel Staffing and Scheduling, Sleep, Sleep Deprivation, Work Schedule Tolerance, Workload, Polysomnography

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