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Cited by 69Sleep and Work-Related FatigueHospital Admissions and OutcomesHealthcare professionals’ stress and burnout

Sleep and Alertness in a Duty-Hour Flexibility Trial in Internal Medicine

Open access
Basner, Mathias, Asch, David A., Shea, Judy A., Bellini, Lisa M., Carlin, Michele, Ecker, Adrian J., Malone, Susan K., Desai, Sanjay V. +13 more·2019·New England Journal of Medicine
DOI 10.1056/nejmoa1810641PMC PMC6457111
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Abstract

Background A purpose of duty‐hour regulations is to reduce sleep deprivation in medical trainees, but their effects on sleep, sleepiness, and alertness are largely unknown. Methods We randomly assigned 63 internal‐medicine residency programs in the United States to follow either standard 2011 duty‐hour policies or flexible policies that maintained an 80‐hour workweek without limits on shift length or mandatory time off between shifts. Sleep duration and morning sleepiness and alertness were compared between the two groups by means of a noninferiority design, with outcome measures including sleep duration measured with actigraphy, the Karolinska Sleepiness Scale (with scores ranging from 1 [extremely alert] to 9 [extremely sleepy, fighting sleep]), and a brief computerized Psychomotor Vigilance Test (PVT‐B), with long response times (lapses) indicating reduced alertness. Results Data were obtained over a period of 14 days for 205 interns at six flexible programs and 193 interns at six standard programs. The average sleep time per 24 hours was 6.85 hours (95% confidence interval [CI], 6.61 to 7.10) among those in flexible programs and 7.03 hours (95% CI, 6.78 to 7.27) among those in standard programs. Sleep duration in flexible programs was noninferior to that in standard programs (between‐group difference, ‐0.17 hours per 24 hours; one‐sided lower limit of the 95% confidence interval, ‐0.45 hours; noninferiority margin, ‐0.5 hours; P=0.02 for noninferiority), as was the score…

Integrity signals

Registry

Crossref · 10.1056/nejmoa1810641

Cites

42 of 42 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

7 of 17 cited sources checked · 4 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    The FIRST Trial found surgical complication and death rates were no worse under flexible duty-hour rules without shift-length restrictions than under standard rules.

    “a national, prospective, cluster-randomized trial of surgical residency programs that showed that surgical-complication and death rates were no worse under flexible duty-hour rules (without restrictions on shift length) than under standard rules.”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [11] source
    • cites [12] source
  • Study design and conductcitation

    The iCOMPARE trial randomly assigned 63 internal-medicine residency programs to maintain 2011 duty-hour standards or use more flexible standards.

    “we created the Individualized Comparative Effectiveness of Models Optimizing Patient Safety and Resident Education (iCOMPARE) trial, a national cluster-randomized trial involving 63 internal-medicine residency programs.19”
    • Also stated in: § CONCLUSIONS · plain
      “Residency programs were randomly assigned either to maintain 2011 duty-hour standards or to use a more flexible set of duty-hour standards”
    Quote in the paperSubstantial claim1 of 1 sources checked
  • Findingown data

    Sleep duration and KSS in flexible programs remained noninferior after Benjamini-Hochberg adjustment for multiple testing.

    “Sleep duration and the score on the Karolinska Sleepiness Scale in flexible programs remained noninferior to those in standard programs at an alpha level of 0.05 after Benjamini–Hochberg adjustments for multiple testing (three comparisons).31”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [31] source
  • Findingown data

    Sleep duration in flexible programs was noninferior to standard programs (difference −0.17 hours; lower 95% CI −0.45; margin −0.5; P=0.02).

    “Sleep duration in flexible programs was noninferior to that in standard programs (between-group difference, −0.17 hours per 24 hours; one-sided lower limit of the 95% confidence interval, −0.45 hours; non-inferiority margin, −0.5 hours; P = 0.02 for non-inferiority)”
    Quote in the paperSubstantial claim
  • Findingown data

    KSS score in flexible programs was noninferior to standard programs (difference 0.12 points; upper 95% CI 0.31; margin 1; P<0.001).

    “scores in flexible programs were noninferior to those in standard programs (between-group difference, 0.12 points; one-sided upper limit of the 95% confidence interval, 0.31 points; non-inferiority margin, 1 point; P<0.001 for noninferiority)”
    Quote in the paperSubstantial claim
  • May combine two claims. 13
  • Classified as probably not a substantial claim. 7

  • May combine two claims.

    Premisecitation

    Sleep loss and night work are linked to lower alertness and cognitive performance and are a safety concern for round-the-clock operations, including medicine.

    “Sleep loss and night work are associated with reduced alertness and cognitive performance1 and represent a safety challenge for all 24/7 operations, including medicine.2–6”
    Quote in the paperSubstantial claim3 of 6 sources checked
    • cites [1] source

      The ‘Chronic sleep restriction induces cumulative neurobehavioral deficits’ section reports declines in alertness and cognitive performance with sleep restriction, with effects most severe during the biological night. That supports the sleep-loss part of the clause cited to this paper, but the passage does not directly establish an effect of night work. The separate safety claim is attached to other citations in the citing sentence. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [2] source
    • cites [3] source

      The Abstract reports that extended shifts pose safety hazards for medical interns and discusses fatigue-related crashes among truck drivers. This supports the safety concern in medicine and another round-the-clock occupation, but the paper does not establish it for all 24/7 operations. The sentence cites a different source for reduced alertness and cognitive performance. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [4] source

      The Discussion reports that extended-duration shifts among US medical interns were associated with attentional failures, medical errors, and preventable adverse events, supporting the safety concern in medicine. The cited paper does not establish that this concern extends to all round-the-clock operations; that broader scope goes beyond the population studied. The alertness and cognitive-performance clause is attached to a different citation. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [5] source
    • cites [6] source

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

    Premisecitation

    Actigraphy is a well-established sleep-wake measurement method and has been used to study physicians' sleep patterns.

    “Actigraphy is a well-established method for sleep–wake measurement23 that has been used to study sleep patterns in physicians.13,24”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites [23] source
    • cites [13] source
    • cites [24] source

  • Classified as probably not a substantial claim.

    Premisecitation

    The PVT-B is a validated measure of vigilant attention stability based on simple reaction time to visual stimuli.

    “The PVT-B is a validated measure of the stability of vigilant attention that is based on simple reaction time to visual stimuli occurring at random intervals”
    Quote in the paperSubstantial claim1 of 1 sources checked

  • May combine two claims.

    Findingown data

    On mornings after extended overnight shifts, PVT-B lapses, KSS score, high KSS percentage, and excessive sleepiness percentage were maximal.

    “The number of PVT-B performance lapses (7.8), the score on the Karolinska Sleepiness Scale (6.8), the percentage of days with a high score (8 or 9) on the Karolinska Sleepiness Scale (38.6%), and the percentage of days on which at least one episode of excessive sleepiness was reported (87.7%) were also maximal on mornings at the end of extended overnight shifts”
    Quote in the paperSubstantial claim

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

    Findingown data

    Data were obtained over 14 days for 205 interns at six flexible programs and 193 interns at six standard programs.

    “Data were obtained over a period of 14 days for 205 interns at six flexible programs and 193 interns at six standard programs.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Sleep duration was shorter on days when interns finished an overnight shift than on days when they worked day shifts, with lower alertness, higher KSS, and more frequent excessive sleepiness, especially between 12 a.m. and 6 a.m.

    “The sleep duration was shorter on days when interns finished an overnight shift than on days when they worked day shifts, with lower levels of alertness, higher scores on the Karolinska Sleepiness Scale, and more frequent reports of excessive sleepiness, especially between 12 a.m. and 6 a.m.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Despite losing more than 1.5 hours of sleep per 24 hours on extended overnight shifts compared with regular day shifts, flexible interns averaged only 10 minutes less sleep per day across the 14-day trial than standard interns.

    “Despite losing more than 1.5 hours of sleep per 24 hours on extended overnight shifts as compared with regular day shifts, interns in flexible programs averaged only 10 minutes less sleep per day across the 14-day trial period than interns in standard programs.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Average sleep time per 24 hours was 6.85 hours (95% CI, 6.61-7.10) in flexible programs and 7.03 hours (95% CI, 6.78-7.27) in standard programs.

    “the average sleep time per 24 hours was 6.85 hours (95% confidence interval [CI], 6.61 to 7.10) among interns in flexible programs and 7.03 hours (95% CI, 6.78 to 7.27) among those in standard programs.”
    Quote in the paperSubstantial claim

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

    Study design and conductnone given

    Limitations include lack of generalizability to interns in smaller internal-medicine programs and in different specialties.

    “Limitations include its lack of generalizability to interns in smaller internal-medicine programs and in different specialties”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Sleep patterns relative to call cycles and the physiological relationship between sleep loss and alertness would not differ for interns in different programs.

  • May combine two claims.

    Study design and conductown data

    Flexible and standard programs did not differ significantly in demographic characteristics or completeness of actigraphy or PVT-B data.

    “Flexible and standard programs did not differ significantly with respect to demographic characteristics or completeness of actigraphy or PVT-B data (Table S4 in the Supplementary Appendix).”
    Quote in the paperNot a substantial claim

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

    Study design and conductown data

    Actigraphy and PVT-B data were classified by sleep experts blinded to trial-group assignments.

    “PVT-B data were inspected and classified as generated in a manner that was adherent with instructions, probably nonadherent, or nonadherent as judged by sleep experts who were not aware of the trial-group assignments”
    Quote in the paperSubstantial claim

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

    Study design and conductown data

    The calculated sample size was 290 interns, assuming 90% power, one-sided type I error 0.05, and a 0.5-hour sleep noninferiority margin; recruitment was increased to 384 to offset data loss.

    “The calculated sample size (with the assumption of 90% power, a one-sided type I error of 0.05, and a noninferiority margin of 0.5 hours of sleep time) was 290 interns. The recruitment goal was increased to 384 interns to mitigate any data loss related to nonadherence and dropouts.”
    Quote in the paperSubstantial claim

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

    Study design and conductnone given

    Strengths of the trial include sample size, objective sleep and alertness measurements, and rigorous blinding through all stages of data collection and analysis.

    “Strengths of this trial include the sample size, objective measurements of sleep (with actigraphy) and alertness (with the PVT-B), and a rigorous blinding through all stages of data collection and analysis.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    Intern sleep duration and sleepiness in flexible programs were noninferior to standard programs, while alertness results did not meet prespecified noninferiority criteria.

    “intern sleep duration and sleepiness in programs that followed flexible duty-hour rules were noninferior to those in programs that followed standard rules, whereas results for alertness did not meet prespecified noninferiority criteria.”
    Quote in the paperSubstantial claim
14 of 14

  • The paper relies on this without support.

    Before this trial, the effects of duty-hour regulations on sleep, sleepiness, and alertness were largely unknown.

    “their effects on sleep, sleepiness, and alertness are largely unknown.”

  • The paper relies on this without support.

    Duty-hour policies are likely to affect trainee education and the sleep and alertness of trainees.

    “In addition to having possible effects on patient safety, duty-hour policies are likely to affect trainee education and the sleep and alertness of trainees.”

  • The paper relies on this without support.

    Sleep patterns relative to call cycles and the physiological relationship between sleep loss and alertness would not differ for interns in different programs.

    “although it is unlikely that sleep patterns relative to call cycles and the physiological relationship between sleep loss and alertness would differ for interns in different programs.”
3 of 3

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?

  • In Basner 2019, recruitment bias was at low risk because the trial reported no recruitment after randomisation.

    “Recruitment bias Low risk Trial reported no recruitment after randomisation.”

    From Adapting shift work schedules for sleep quality, sleep duration, and sleepiness in shift workers (2023) · cites this paper as Basner 2019

    The trial description says residency programs were randomly assigned to duty-hour policies. The Methods (Trial Procedures and Participants; page not supplied) then describes coordinators recruiting interns at those programs, including programs already assigned to flexible rules. This contradicts the claim that no recruitment occurred after randomisation; the paper does not itself assess recruitment-bias risk. (LLM, conf=0.88)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • Participants who worked overnight shifts lasting no longer than 16 hours slept more hours per week (Barger 2019a) or during overnight shifts (Basner 2019) than those who worked 24 to 28 hour shifts.

    “Participants who worked overnight shifts lasting no longer than 16 hours slept more hours per week (in Barger 2019a) or during (over)night shifts (in Basner 2019) than those who worked overnight shifts of 24 to 28 hours.”

    From Adapting shift work schedules for sleep quality, sleep duration, and sleepiness in shift workers (2023) · cites this paper as Basner 2019

    The Results section (Analyses Stratified According to Shift Type; page unavailable) reports 7.35 hours of sleep on night-shift days in standard programs versus 5.12 hours during extended overnight shifts in flexible programs. But it says the groups slept similar amounts during the night; the standard-program advantage came largely from sleep during the day after the shift. Thus the finding supports more sleep on night-shift days, not more sleep during the overnight shifts themselves. The passages do not specify that the extended shifts lasted 24 to 28 hours. (LLM, conf=0.88)

    Experimental — accuracy not yet measured

  • Only the two RCTs investigating 80-hour workweeks included a substantial number of women and were conducted in the healthcare sector (Barger 2019a; Basner 2019).

    “Only the two RCTs investigating the 80‐hour workweeks included a substantial number of women and were conducted in the healthcare sector (Barger 2019a; Basner 2019).”

    From Adapting shift work schedules for sleep quality, sleep duration, and sleepiness in shift workers (2023) · cites this paper as Basner 2019

    The Methods and Discussion describe a randomized trial of internal-medicine interns under an 80-hour weekly work limit, supporting the healthcare-setting and workweek parts of the claim. The Results give 398 interns in total but do not state how many were women; the paper also cannot establish that these were the only two RCTs with those characteristics. (LLM, conf=0.83)

    Experimental — accuracy not yet measured

  • In Basner 2019, selective reporting was at low risk of bias because all outcomes prespecified in the protocol were reported.

    “Selective reporting (reporting bias) Low risk All outcomes prespecified in the protocol were reported.”

    From Adapting shift work schedules for sleep quality, sleep duration, and sleepiness in shift workers (2023) · cites this paper as Basner 2019

    The Methods (Statistical Analysis; page unavailable) identify three primary sleep and alertness outcomes, and the Results (Noninferiority Analyses; page unavailable) report them. The paper refers to its protocol but does not establish that every outcome prespecified in it was reported, so the stated basis for a low-risk selective-reporting judgment is not fully supported by our copy. (LLM, conf=0.78)

    Experimental — accuracy not yet measured

  • In Basner 2019, random sequence generation was at low risk of bias because valid random sequence generation was used.

    “Random sequence generation (selection bias) Low risk Valid random sequence generation.”

    From Adapting shift work schedules for sleep quality, sleep duration, and sleepiness in shift workers (2023) · cites this paper as Basner 2019

    The Methods section (Trial Procedures and Participants; page unavailable) says programs were randomly assigned to flexible duty-hour rules. It does not describe how the random sequence was generated, so the claim that sequence generation was valid and therefore at low risk of bias is not established by our copy. (LLM, conf=0.82)

    Experimental — accuracy not yet measured

Cites

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Related

Authors
Basner, M., Asch, D. A., Shea, J. A., Bellini, L. M., Carlin, M., Ecker, A. J., Malone, S. K., Desai, S. V., Sternberg, A. L., Tonascia, J., Shade, D. M., Katz, J. T., Bates, D. W., Even-Shoshan, O., Silber, J. H., Small, D. S., Volpp, K. G., Mott, C. G., Coats, S., Mollicone, D. J., & Dinges, D. F.
Affiliations
  • Children's Hospital of Philadelphia (US)
  • Brigham and Women's Hospital (US)
  • From the University of Pennsylvania (M.B., D.A.A., J.A.S., L.M.B., M.C., A.J.E., S.K.M., D.S.S., K.G.V., D.F.D.), Corporal Michael J. Crescenz Veterans Affairs Medical Center (D.A.A., K.G.V.), Children’s Hospital of Philadelphia (O.E.-S., J.H.S.), and Pulsar Informatics (C.G.M., S.C., D.J.M.) — all in Philadelphia; Johns Hopkins University, Baltimore (S.V.D., A.L.S., J.T., D.M.S.); and Brigham and Women’s Hospital, Boston (J.T.K., D.W.B.).
ORCID
Venue
New England Journal of Medicine
Publisher
Massachusetts Medical Society
Published
2019-03-07
Volume
380
Issue
10
Pages
915-923
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
DOI
10.1056/nejmoa1810641
PMC
PMC6457111
OpenAlex
W2921696036
Cited by
69
References
42
Citations by year
2026: 7 · 2025: 6 · 2024: 8 · 2023: 10 · 2022: 12 · 2021: 12 · 2020: 6 · 2019: 7
FWCI
10.88
Type
journal article
Language
en
Open access
Licence
www.nejmgroup.org/legal/terms-of-use.htm (vor)
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • National Heart, Lung, and Blood Institute (U01HL126088, U01HL125388)
  • National Institute of Nursing Research (P20NR018075, F31NR014603, K99NR017416)
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
duty hour regulations, sleep deprivation, sleep duration, sleepiness, alertness, medical interns, internal medicine residency, Karolinska Sleepiness Scale, psychomotor vigilance test, non-inferiority, shift length, physician fatigue, medical education policy, actigraphy
MeSH terms
Sleepiness, Humans, Internal Medicine, Internship and Residency, Personnel Staffing and Scheduling, Sleep, Sleep Deprivation, United States, Wakefulness, Work Schedule Tolerance, Actigraphy

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Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

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Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-09-28.

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