The effectiveness of driver improvement suspension was evaluated relative to 4 alternatives: No contact, a last-change warning letter, a probationary license, and a Defensive Driving Course. Drivers were randomly assigned to these 5 conditions with the exception that the Defensive Driving Course was available only in the largest metropolitan areas of Oregon. The proportion of drivers in each group who were able to drive 1 full year without a moving violation or chargeable accident was compared among the groups. A final sample of 932 drivers' records was analyzed. Drivers in the probationary license and DDC groups had significantly superior driving records in the follow-up year than did the suspension group. The probationary license also appeared to have a significant delaying effect on the occurrence of subsequent traffic citations or culpable collisions. The overall evidence argued for more extensive use of probationary licenses and the Defensive Driving Course. This conclusion does not imply the discontinuation of suspension as a driver improvement device, since it is likely that the effectiveness of both the probationary license and the DDC might be at least partially due to the presence of suspension as a less desirable alternative.

  • Availability:
  • Supplemental Notes:
    • Project jointly sponsored by NHTSA and Oregion DOT, Research work done by Oregon Traffic Safety Commission, Willamette University and Oregon Alcohol Safety Action Project.
  • Corporate Authors:

    National Safety Council

    425 North Michigan Avenue
    Chicago, IL  United States  60611
  • Authors:
    • Kaestner, N
    • Speight, L
  • Publication Date: 1975-6

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00098807
  • Record Type: Publication
  • Source Agency: Highway Safety Research Institute
  • Report/Paper Numbers: DL 70-001(001-003)
  • Files: TRIS
  • Created Date: Oct 18 1975 12:00AM