title: Carrying passengers as a risk factor for crashes fatal to 16- and 17-year-old drivers.
abstract: BACKGROUND
  Injuries from motor vehicle crashes are the leading cause of death among teenagers. Carrying passengers has been identified as a possible risk factor for these crashes.
  
  
  OBJECTIVE
  To determine whether the presence of passengers is associated with an increased risk of crashes fatal to 16- and 17-year-old drivers and whether the risk varies by time of day and age and sex of drivers and passengers. DESIGN AND SETTING INCIDENCE: study of data from the Fatality Analysis Reporting System and General Estimates System (1992-1997), as well as the Nationwide Personal Transportation Survey (1995).
  
  
  METHODS
  Drivers aged 16 and 17 years who drove passenger cars, vans, or pickup trucks.
  
  
  METHODS
  Driver deaths per 10 million trips by number of passengers, driver age and sex, and time of day; and driver deaths per 1000 crashes by passenger age and sex.
  
  
  RESULTS
  Compared with drivers of the same age without passengers, the relative risk of death per 10 million trips was 1.39 (95% confidence interval [CI], 1.24-1.55) for 16-year-old drivers with 1 passenger, 1.86 (95% CI, 1.56-2.20) for those with 2 passengers, and 2.82 (95% CI, 2.27-3.50) for those with 3 or more passengers. The relative risk of death was 1.48 (95% CI, 1.35-1.62) for 17-year-old drivers with 1 passenger, 2.58 (95% CI, 2.24-2.95) for those with 2 passengers, and 3.07 (95% CI, 2.50-3.77) for those with 3 or more passengers. The risk of death increased significantly for drivers transporting passengers irrespective of the time of day or sex of the driver, although male drivers were at greater risk. Driver deaths per 1000 crashes increased for 16- and 17-year-olds transporting male passengers or passengers younger than 30 years.
  
  
  CONCLUSIONS
  Our data indicate that the risk of fatal injury for a 16- or 17-year-old driver increases with the number of passengers. This result supports inclusion of restrictions on carrying passengers in graduated licensing systems for young drivers.
authors.affiliation: Center for Injury Research and Policy, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205-1996, USA. lhchen@jhsph.edu
authors.forename: L H
authors.initials: LH
authors.lastname: Chen
authors.forename: S P
authors.initials: SP
authors.lastname: Baker
authors.forename: E R
authors.initials: ER
authors.lastname: Braver
authors.forename: G
authors.initials: G
authors.lastname: Li
mesh_terms: D000063:Accidents, Traffic / Q000401:mortality*; D000293:Adolescent; D000328:Adult; D001334:Automobile Driving / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D012307:Risk Factors; D014481:United States / Q000453:epidemiology