Impact of Partial Graduated Driver’s License Program on Teen Motor Vehicle Crashes in Kentucky

Abstract

Teen-driver motor vehicle crashes (MVCs), MVC-related injuries, and MVC-related costs before (1993-1995) and after (1997-1999) the implementation of the teen driver licensing (TDL) program in Kentucky are evaluated. Data collected as part of the study are used to recommend actions to enhance the effectiveness of Kentucky’s TDL program. The study involved the analysis of teen crash data pre-TDL and post-TDL by using data from the Kentucky Accident Reporting System database and the Kentucky Transportation Cabinet driver license file. The study also involved analysis of crash data in relation to crash costs by using the CrashCost software program. Findings indicate that implementation of the TDL program in Kentucky resulted in a substantial (32 percent) reduction in MVC rates for 16-year-old drivers from before the TDL program and a similar reduction in crashes after midnight, fatal crashes, and injury crashes for the 16-year-old age group. Cost analysis indicates an estimated annual reduction of $34.2 million in 16-year-old teen-driver MVC-related expenses. However, after a dramatic reduction in the number of crashes for ages 16 to 16.5 (learner permit stage), the number of crashes rose sharply for ages 16.5 to 17, when drivers may have progressed to independent driving. There were no decreases in crash rates for 17- and 18-year-old drivers under the TDL program. Results from this study indicate a need for more effective measures to decrease MVCs for ages 16.5 to 18, such as upgrading to a full graduated driver licensing program.

Kentucky's graduated driver licensing program for young drivers: barriers to effective local implementation

“…1 Results indicate a 32% reduction in crash rates for 16 year old drivers due to an 83% decrease in crash rates for drivers age 16 to 16 1 ⁄2, the age that drivers are in the adult supervised permit level. Unfortunately, there have been no decreases in the number of crashes for drivers over age 16 1 ⁄2.…”

“…Results from this study indicate a need for additional measures to decrease motor vehicle crashes in the 16 1 ⁄2 to 18 year old age group. 1 Research evaluating GDL programs in most jurisdictions indicates that teen crashes have decreased significantly after implementation of GDL programs. [5][6][7][8][9][10][11][12][13][14] However, studies also indicate that the eVect on 17 and 18 year old drivers varies greatly among jurisdictions, from a substantial reduction (17% in Nova Scotia 6 ), to an increase (6% in Kentucky 1 ).…”

“…15 19-21 Analysis of Kentucky crash data involving drivers age 16 to 16 1 ⁄2 after GDL verifies that there is substantial noncompliance with permit level provisions, such as the night-time driving restriction and the adult supervision requirement. 1 Research in New Zealand indicates that non-compliance and low level of oYcial enforcement have a significant influence on GDL eVectiveness. 15 22 Survey results in Ontario and Nova Scotia revealed that a substantial number of permit drivers (15% to 30%) reportedly drove only two or less times per month in the learning stage of GDL.…”

“…During 1995-99, teen drivers were associated with 24% of injury crashes in the state, despite representing only 6.4% of licensed drivers. 1 Thirty two states have attempted to address this problem though graduated driver licensing (GDL) programs. 2 This legislation extends the supervised learning period to improve driving skills and decision making, imposes restrictions to help protect young drivers from hazardous situations while they learn to drive, and applies penalties to motivate young drivers to drive safely.…”

Graduated driver licensing: what works?

“…In Kentucky, Agent and colleagues 15 reported a 32% per driver decline in crashes of 16 year olds over the three years following introduction of GDL. This effect was attributable primarily to an 83% crash reduction among those aged 16 to 16 years 6 months, who would necessarily be driving on a learner permit.…”