DDC Resources: Evidence

Title:

College of Lake County Driver Safety Program: 1996 Follow-Up Evaluation

Author:

Kennedy, ME

Summary:

• Course: DDC (4 hours)
• Setting: 19th Judicial Circuit Court (Lake Co., Illinois)
• Population: Drivers convicted of a singular traffic offense who have not been placed under court supervision for any traffic violation committed within the past 12 months.
• Intervention group: 1,500 drivers who completed DDC as a result of being convicted of a moving violation in 1991
• Control group: 1,500 drivers ticketed in 1990 for similar violations before DDC became available
• Study period: 3.5 years post course completion
• Major findings: Statistically significant 13% reduction in negligent driving violations and 9% reduction in crashes among DDC participants compared to control-group drivers

Full Text Report:

College of Lake County Driver Safety Program: 1996 Follow-Up Evaluation

Title:

Lake County, Illinois Defensive Driving Course: 1999 Driver Safety Training Program Evaluation

Author:

Kennedy, ME

Summary:

• Course: DDC (4 hours)
• Setting: 19th Judicial Circuit Court (Lake Co., Illinois)
• Population: Drivers convicted of a singular traffic offense who have not been placed under court supervision for any traffic violation committed within the past 12 months.
• Intervention group: 400 drivers who completed DDC as a result of being convicted of a moving violation in 1991
• Control group: 400 drivers ticketed in 1990 for similar violations before DDC became available
• Study period: nine years after course completion
• Major findings: Over a nine-year period, control-group drivers were eight times more likely to be involved in a crash and 10 times more likely to be arrested for a moving violation than drivers who participated in DDC.

Full Text Report:

Lake County, Illinois Defensive Driving Course: 1999 Driver Safety Training Program Evaluation

Title:

Recorded Traffic Offenses of Graduates of Traffic Safety School, Cook County, Illinois

Author:

Northwestern University Traffic Institute

Summary:

• Course: DDC (4 hours)
• Setting: District Court of Cook County, Illinois
• Population: Drivers who had committed their first driving offense
• Intervention group: 452 drivers who in 1994 pleaded guilty to a moving violation and requested DDC in lieu of a trial
• Control group: 488 who in 1994 pleaded guilty to a moving violation, requested DDC in lieu of a trial, but did not take DDC
• Study period: 24 months (12 months before and after course completion) and three years after course completion
• Major findings: Drivers who received DDC were significantly less likely to be pulled over for a traffic violation and less likely to receive a traffic citation within 12 months of training compared to the control group. The study showed that the intervention-control group differences in the number of citations became non-significant after the first four months. Within three years of training, however, control-group drivers received 37% more citations than the intervention group.

Full Text Report:

Recorded Traffic Offenses of Graduates of Traffic Safety School, Cook County, Illinois

Title:

Incident Experience of Indiana Drivers Before and After Participation in the Defensive Driving Course Program During the Calendar Year 1994

Author:

Research and Statistics Department, National Safety Council

Summary:

• Course: DDC (6 and 8 hours)
• Setting: State of Indiana
• Population: Drivers convicted of two or more traffic offenses within a 12-month period
• Intervention Group: 10,726 drivers who completed DDC in 1994
• Control Group: N/A
• Study Period: 24 months (12 months before and after course completion)
• Major Findings: DDC participants showed a statistically significant decline in points (63% reduction), infractions (57% reduction) and misdemeanors (40% reduction) in the year after exposure to DDC compared with the year before. The number of recorded crashes was insufficient to enable a statistical analysis.

Full Text Report:

Incident Experience of Indiana Drivers Before and After Participation in the Defensive Driving Course Program During the Calendar Year 1994

Title:

The Surchargeable Incident Experience of Massachusetts Drivers Before and After Participation in the DDC-Attitudinal Dynamics of Driving Course

Author:

Research and Statistics Department, National Safety Council

Summary:

• Course: DDC-ADD (8 hours)
• Setting: Commonwealth of Massachusetts
• Population: Drivers who were subject to license suspension for accumulating five surchargeable incidents (i.e., at-fault crashes and moving violations) within a three-year period
• Intervention group: 3,545 drivers who completed DDC in 1996
• Control group: N/A
• Study period: 12 months (six months before and after course completion)
• Major findings: DDC participants showed a statistically significant decline in minor traffic violations (49% reduction), major traffic violations (44% reduction) and surchargeable incidents (41% reduction) in the six months after exposure to DDC compared with the six-month period before. The improvement among female drivers was greater compared with their male counterparts across the three violation categories.

Full Text Report:

The Surchargeable Incident Experience of Massachusetts Drivers Before and After Participation in the DDC-Attitudinal Dynamics of Driving Course

Title:

Incident Experience of Massachusetts Drivers Before and After Participation in the DDC-Attitudinal Dynamics of Driving Course

Author:

Research and Statistics Department, National Safety Council

Summary:

• Course: DDC-ADD (8 hours)
• Setting: Commonwealth of Massachusetts
• Population: Drivers who were subject to license suspension for accumulating five surchargeable incidents (i.e., at-fault crashes and moving violations) within a three-year period
• Intervention group: 4,762 drivers who completed DDC in 2007
• Control group: N/A
• Study period: 24 months (12 months before and after course completion)
• Major findings: DDC participants showed a statistically significant decline in minor traffic violations (71% reduction), major traffic violations (64% reduction) and surchargeable incidents (73% reduction) in the six months after exposure to DDC compared with the six-month period before. Judging by the magnitude of change in violations and crashes, older drivers (65+ years) appeared to benefit more from exposure to DDC compared to younger drivers.

Full Text Report:

Incident Experience of Massachusetts Drivers Before and After Participation in the DDC-Attitudinal Dynamics of Driving Course

Title:

Incident Experience of Massachusetts Drivers Before and After Participation in the DDC-Attitudinal Dynamics of Driving Course

Author:

Research and Statistics Department, National Safety Council

Summary:

• Course: DDC-ADD (8 hours)
• Setting: Commonwealth of Massachusetts
• Population: Drivers who were subject to license suspension for accumulating three surchargeable incidents (i.e., at-fault crashes and moving violations) within a two-year period
• Intervention group: 47,513 drivers who completed DDC in 2012
• Control group: N/A
• Study period: four years (one year before and three years after course completion)
• Major findings: All DDC participants, regardless of age or gender, had significantly fewer violations in each of the three years after completing DDC than in the year before. Compared to the year before training, minor traffic violations, major violations and surchargeable incidents showed statistically significant declines of 84%, 78% and 88%, respectively, during the three-year follow-up period.

Full Text Report:

Incident Experience of Massachusetts Drivers Before and After Participation in the DDC-Attitudinal Dynamics of Driving Course

Title:

Incident Experience of Massachusetts Drivers Before and After Participation in Attitudinal Dynamics of Driving Defensive Driving Course

Author:

Research and Statistics Department, National Safety Council

Summary:

• Course: DDC-ADD (8 hours)
• Setting: Commonwealth of Massachusetts
• Population: Drivers who were subject to license suspension for accumulating three surchargeable incidents (i.e., at-fault crashes and moving violations) within a two-year period
• Intervention group: 41,186 drivers who completed DDC in 2017
• Control group: N/A
• Study period: three years (one year before and two years after course completion)
• Major findings: All DDC participants had significantly fewer total violations and lower violation rates in each of the two post training years than in the year before training. DDC participants showed a statistically significant decline in the total number of traffic violations (65% reduction), minor violations (69%), major violations (55%) and surchargeable incidents (77%) in the two years after exposure to DDC compared with the one-year period before. These findings are consistent with the magnitude of safety improvements observed in the previously conducted studies involving Massachusetts drivers.

Full Text Report:

Incident Experience of Massachusetts Drivers Before and After Participation in Attitudinal Dynamics of Driving Defensive Driving Course

Title:

Incident Experience of Massachusetts Drivers Before and After Participation in the Defensive Driving Online Course

Author:

Research and Statistics Department, National Safety Council

Summary:

• Course: DDC Online (6 hours)
• Setting: Commonwealth of Massachusetts
• Population: Drivers who were subject to license suspension for accumulating five surchargeable incidents (i.e., at-fault crashes and moving violations) within a three-year period
• Intervention group: 31,654 drivers who completed DDC Online in 2020
• Control group: N/A
• Study period: 24 months (twelve months before and after course completion)
• Major findings: Drivers who participated in the DDC Online course, experienced a decrease in monthly average violation rates per 100 drivers in the year following training compared to the year before training. However, the magnitude of the decrease across all violation types varied: total violations dropped by 71%, minor violations by 74%, major violations by 38%, and surchargeable violations by 74%. In addition, DDC Online participants also experienced statistically lower monthly average crash-related surchargeable violation rates per 100 drivers the year following training compared to the year before training (2.8 crash-related surchargeable violations before and 0.82 after training, a 71% decrease).

Full Text Report:

Incident Experience of Massachusetts Drivers Before and After Participation in the Defensive Driving Online Course

Title:

Traffic Diversion Programs: Are They Effective? A Comprehensive Look at the Recidivism Rates of Traffic Offenders who Attend an Eight-hour and Four-hour Defensive Driving Course

Author:

University of Nebraska at Omaha

Summary:

• Course: DDC (4 and 8 hours)
• Setting: Douglas County, NE
• Population: Drivers who received a traffic citation and were eligible to take DDC to dismiss the violation
• Intervention group: (Group A) – 249 drivers who were ticketed for a traffic violation in 2003 and completed DDC-4 to dismiss the violation; (Group B) – 249 drivers who were ticketed for a traffic violation in 2004 and completed DDC-8 to dismiss the violation
• Control group: (Group A) – 249 drivers who were ticketed for a traffic violation in 2003 and chose to pay a fine/accrue points on the driving record; (Group B) – 249 drivers who were ticketed for a traffic violation in 2004 and chose to pay a fine/accrue points on the driving record
• Study period: one year and three years
• Major findings: After one year, DDC participants (Groups A and B) were nearly two times less likely to have a traffic violation compared to the control groups (14.7% among DDC participants versus 26.9% among controls). After three years, DDC participants (Groups A and B) were nearly two times less likely to have a traffic violation compared to the control groups (32.9% among DDC participants versus 55.8% among controls). There were no statistically significant differences in recidivism rates between DDC-4 and DDC-8 students

Full Text Report:

Traffic Diversion Programs: Are They Effective? A Comprehensive Look at the Recidivism Rates of Traffic Offenders who Attend an Eight-hour and Four-hour Defensive Driving Course

Title:

New York State Effectiveness Study of the I-PIRP Pilot

Author:

Institute for Traffic Safety Management and Research, University at Albany

Summary:

• Course: Defensive driving courses offered by 11 providers, including NSC
• Setting: New York State
• Population: Drivers who choose to complete DDC as a way to receive a driving record point reduction and/or auto insurance premium reduction
• Intervention group: (Group A) – 3,000 drivers who competed DDC online in 2010; (Group B) – 3,000 drivers who competed classroom-based DDC in 2010;
• Control group: N/A
• Study period: 36 months (18 months before and after course completion)
• Major findings: There was a statistically significant reduction in the number of convictions among drivers who completed DDC online (22% before versus 17% after DDC). There was a statistically significant reduction in the number of crashes among drivers who completed DDC online (9.6% before versus 8.0% after DDC). There was a statistically significant reduction in the number of convictions among drivers who completed DDC in the classroom (20% before versus 16% after DDC). For classroom-based DDC participants, the observed reduction in crashes was not statistically significant (9.3% before versus 8.8 after DDC). There were no statistically significant differences in convictions or crashes between those who completed DDC online and in the classroom.

Full Text Report:

New York State Effectiveness Study of the I-PIRP Pilot

Title:

Study of Recidivism Rates among Drivers Administratively Sanctioned by the New Jersey Motor Vehicle Commission

Author:

Alan M. Voorhees Transportation Center, Rutgers University

Summary:

• Course: DDC-ADD (4 hours)
• Setting: State of New Jersey
• Population: Drivers with 12-14 points on their driving record in more than two years
• Intervention group: (Group A) - 5,517 drivers ages 18+ years who between 2002 and 2004 completed a Driver Improvement Program followed by 1-year probation; (Group B) – 4,027 teen drivers (ages 16-17 years) who between 2002 and 2004 completed a probationary driver program followed by one-year probation
• Control group: N/A
• Study period: 48 months (24 months before and after course completion)
• Major findings: All DDC participants, regardless of age or gender, had significantly lower violation rates in the two years following DDC training compared with the prior two-year period. The rate of decline varied from 18% among male teen drivers to 32% among male drivers aged 18-24 years and female teen drivers. The average time between DDC completion and repeat violations was 306 days for drivers aged 18+ years and 298 days for teen drivers. A comparison of crash rates before and after DDC showed a statistically significant decline among male drivers aged 18-24 years but not among other demographic groups. The average time between DDC completion and repeat crashes was 337 days for teens and 325 days for drivers 18 and older.

Full Text Report:

Study of Recidivism Rates among Drivers Administratively Sanctioned by the New Jersey Motor Vehicle Commission

Title:

Alive at 25: Analysis for North Dakota Teen Drivers

Author:

Upper Great Plains Transportation Institute, North Dakota State University

Summary:

• Course: Alive at 25 (4 hours)
• Setting: State of North Dakota
• Population: Drivers under the age of 25 who were ordered by court or DOT to participate in Alive at 25 and also those who did so voluntarily for an insurance discount or point reduction
• Intervention Group: 6,640 North Dakota drivers who completed Alive at 25 between 2008 and 2014 and whose license, crash, and conviction records were successfully matched
• Control Group: N/A
• Study Period: 6, 12, and 24-month intervals before and after course completion
• Major Findings: For licensed drivers, there were statistically significant reductions in crashes, citations, and DUI arrests for the 6- and 12-month before-and-after intervals. For the 24-month comparison, only crashes and citations showed statistically significant reductions, but not DUI arrests.

Full Text Report:

Alive at 25: Analysis for North Dakota Teen Drivers

Title:

Study of the Effectiveness of Basic Driver Improvement Courses

Author:

Division of Driver Licenses, Florida Department of Highway Safety and Motor Vehicles

Summary:

• Course: DDC Online (4 hours)
• Setting: State of Florida
• Population: Drivers who participated in DDC as a result of a moving violation
• Intervention group: 1,000 drivers who completed DDC before 2014
• Control group: 1,000 drivers matched on age, gender, geographic location, traffic citations, and crashes who did not complete DDC
• Study period: 36 months (18 months before and after course completion)
• Major findings: DDC participants showed a statistically significant reduction in violations following DDC completion compared to control-group drivers

Full Text Report:

Study of the Effectiveness of Basic Driver Improvement Courses

Title:

Study of the Effectiveness of Basic Driver Improvement Courses

Author:

Division of Driver Licenses, Florida Department of Highway Safety and Motor Vehicles

Summary:

• Course: DDC Online (4 hours)
• Setting: State of Florida
• Population: Drivers who participated in DDC as a result of a moving violation
• Intervention group: 1,000 drivers who completed DDC before 2019
• Control group: 1,000 drivers matched on age, gender, geographic location, traffic citations, and crashes who did not complete DDC
• Study period: 36 months (18 months before and after course completion)
• Major findings: DDC participants showed a statistically significant reduction in violations following DDC completion compared to control-group drivers

Full Text Report:

Division of Driver Licenses, Florida Department of Highway Safety and Motor Vehicles

Title:

What is the Effect of Driver Education Programs on Traffic Crash and Violation Rates

Author:

Sun Consulting

Summary:

• Course: DDC (4 hours)
• Setting: State of Arizona
• Population: Drivers subject to license suspension for a moving violation
• Intervention group: 21,131 drivers with a citation for a moving violation who were referred to and completed DDC training in 2001
• Control group: 129,433 drivers with a citation for a moving violation who were not referred to take DDC in 2001
• Major findings: Fewer DDC participants received another citation within 18 months of course completion than control-group drivers (25% vs. 29%). When crash citation rates were compared before and after DDC completion, DDC participants showed a greater decline in the proportion of cited drivers (18.7% before and 4.0% after; 79% decline) compared to control-group drivers (7.2% before and 3.7% after; 49% decline). The study findings were complicated by a large percentage of traffic offenders who were referred to take driver improvement training but did not complete it, choosing license suspension instead.

Full Text Report:

What is the Effect of Driver Education Programs on Traffic Crash and Violation Rates

Title:

Accident prevention versus recidivism prevention courses for repeat traffic offenders

Author:

National Public Services Research Institute

Summary:

• Course: DDC (4 hours)
• Setting: Maricopa and Pima Counties
• Population: Drivers who accumulate eight or more points on their record
• Intervention group: (Group A) – 8,989 drivers who completed Traffic Survival School/Accident Prevention Course (TSS/APC) in 1989-90; (Group B) – 7,804 drivers who completed Traffic Violator School/Recidivism Prevention Course (TVS/RPC) in 1989-90
• Control group: N/A
• Major findings: When violation rates were compared before and after training completion, both groups showed a decline in the proportion of cited drivers (TSS/APC – 2.40 before and 0.399 after; 83.4% decline vs. TVS/RPC – 2.38 before and 0.368 after; 84.5% decline). When crash rates were compared before and after training completion, both groups showed a decline in the proportion of crash-involved drivers (TSS/APC – 1.161 before and 0.033 after; 97.2% decline vs. TVS/RPC – 1.165 before and 0.0.027 after; 97.7% decline). The study findings were complicated by a large percentage of traffic offenders who were referred to take driver improvement training but did not complete it, choosing license suspension instead.

Full Text Report:

Accident prevention versus recidivism prevention courses for repeat traffic offenders