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. 2001 Sep;7(3):194–199. doi: 10.1136/ip.7.3.194

Drowsiness, counter-measures to drowsiness, and the risk of a motor vehicle crash

P Cummings 1, T Koepsell 1, J Moffat 1, F Rivara 1
PMCID: PMC1730738  PMID: 11565983

Abstract

Objectives—Knowledge of how different indicators of drowsiness affect crash risk might be useful to drivers. This study sought to estimate how drowsiness related factors, and factors that might counteract drowsiness, are related to the risk of a crash.

Methods—Drivers on major highways in a rural Washington county were studied using a matched case-control design. Control (n=199) drivers were matched to drivers in crashes (n=200) on driving location, travel direction, hour, and day of the week.

Results—Crash risk was greater among drivers who felt they were falling asleep (adjusted relative risk (aRR) 14.2, 95% confidence interval (CI) 1.4 to 147) and those who drove longer distances (aRR 2.2 for each additional 100 miles, 95% CI 1.4 to 3.3). Risk was also greater among drivers who had slept nine or fewer hours in the previous 48 hours, compared with those who had slept 12 hours. Crash risk was less for drivers who used a highway rest stop (aRR 0.5, 95% CI 0.3 to 1.0), drank coffee within the last two hours (aRR 0.5, 95% CI 0.3 to 0.9), or played a radio while driving (aRR 0.6, 95% CI .4 to 1.0).

Conclusion—Drivers may be able to decrease their risk of crashing if they: (1) stop driving if they feel they are falling asleep; (2) use highway rest stops; (3) drink coffee; (4) turn on a radio; (5) get at least nine hours sleep in the 48 hours before a trip; and (6) avoid driving long distances by sharing the driving or interrupting the trip.

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Selected References

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  1. Greenland S. Dose-response and trend analysis in epidemiology: alternatives to categorical analysis. Epidemiology. 1995 Jul;6(4):356–365. doi: 10.1097/00001648-199507000-00005. [DOI] [PubMed] [Google Scholar]
  2. Horne J. A., Reyner L. A. Counteracting driver sleepiness: effects of napping, caffeine, and placebo. Psychophysiology. 1996 May;33(3):306–309. doi: 10.1111/j.1469-8986.1996.tb00428.x. [DOI] [PubMed] [Google Scholar]
  3. Horne J. A., Reyner L. A. Sleep related vehicle accidents. BMJ. 1995 Mar 4;310(6979):565–567. doi: 10.1136/bmj.310.6979.565. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Johns M. W. A new method for measuring daytime sleepiness: the Epworth sleepiness scale. Sleep. 1991 Dec;14(6):540–545. doi: 10.1093/sleep/14.6.540. [DOI] [PubMed] [Google Scholar]
  5. Johns M. W. Daytime sleepiness, snoring, and obstructive sleep apnea. The Epworth Sleepiness Scale. Chest. 1993 Jan;103(1):30–36. doi: 10.1378/chest.103.1.30. [DOI] [PubMed] [Google Scholar]
  6. Lyznicki J. M., Doege T. C., Davis R. M., Williams M. A. Sleepiness, driving, and motor vehicle crashes. Council on Scientific Affairs, American Medical Association. JAMA. 1998 Jun 17;279(23):1908–1913. doi: 10.1001/jama.279.23.1908. [DOI] [PubMed] [Google Scholar]
  7. McCartt A. T., Ribner S. A., Pack A. I., Hammer M. C. The scope and nature of the drowsy driving problem in New York State. Accid Anal Prev. 1996 Jul;28(4):511–517. doi: 10.1016/0001-4575(96)00021-8. [DOI] [PubMed] [Google Scholar]
  8. Mickey R. M., Greenland S. The impact of confounder selection criteria on effect estimation. Am J Epidemiol. 1989 Jan;129(1):125–137. doi: 10.1093/oxfordjournals.aje.a115101. [DOI] [PubMed] [Google Scholar]
  9. Pack A. I., Pack A. M., Rodgman E., Cucchiara A., Dinges D. F., Schwab C. W. Characteristics of crashes attributed to the driver having fallen asleep. Accid Anal Prev. 1995 Dec;27(6):769–775. doi: 10.1016/0001-4575(95)00034-8. [DOI] [PubMed] [Google Scholar]
  10. Reyner L. A., Horne J. A. Evaluation "in-car" countermeasures to sleepiness: cold air and radio. Sleep. 1998;21(1):46–50. [PubMed] [Google Scholar]
  11. Reyner L. A., Horne J. A. Falling asleep whilst driving: are drivers aware of prior sleepiness? Int J Legal Med. 1998;111(3):120–123. doi: 10.1007/s004140050131. [DOI] [PubMed] [Google Scholar]
  12. Sagberg F. Road accidents caused by drivers falling asleep. Accid Anal Prev. 1999 Nov;31(6):639–649. doi: 10.1016/s0001-4575(99)00023-8. [DOI] [PubMed] [Google Scholar]
  13. Terán-Santos J., Jiménez-Gómez A., Cordero-Guevara J. The association between sleep apnea and the risk of traffic accidents. Cooperative Group Burgos-Santander. N Engl J Med. 1999 Mar 18;340(11):847–851. doi: 10.1056/NEJM199903183401104. [DOI] [PubMed] [Google Scholar]

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