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A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
Potential risk of using General Estimates System: bicycle safety
1Virginia Transportation Research Council, Virginia Department of Transportation, 530 Edgemont Road, Charlottesville, VA 22903, United States. Young-Jun.Kweon@VDOT.Virginia.gov
Accident; Analysis and Prevention
|August 24, 2010
Summary
The United States General Estimates System (GES) database may provide unreliable data for studying bicycle helmet effectiveness due to inconsistent results and potential underrepresentation. Caution is advised when interpreting traffic safety studies using this dataset.
Area of Science:
- Transportation Safety
- Epidemiology
- Data Analysis
Background:
- Previous studies on bicycle helmet benefits primarily used hospital or survey data.
- The United States General Estimates System (GES) database is widely used by transportation professionals.
- Concerns exist regarding the reliability of large databases for narrowly focused safety research.
Purpose of the Study:
- To assess the validity of the GES database for evaluating bicycle helmet effectiveness in reducing injury severity.
- To identify potential risks of drawing erroneous conclusions from GES data in traffic safety studies.
Main Methods:
- Analysis of approximately 16,000 bicycle-involved traffic crash records from the GES database (2003-2008).
- Utilized a partial proportional odds model to analyze injury severity.
- Examined year-to-year variations in helmet use rates and injury effects.
Main Results:
- Inconsistent findings regarding helmet effectiveness: beneficial in 2007, detrimental in 2004, and no effect in other years.
- Significant fluctuations in average helmet use rates (12% to 38%) suggest potential data underrepresentation.
- Results contradict previous findings based on medical or hospital survey data.
Conclusions:
- The GES database may not be a reliable source for studying specific issues like bicycle helmet effectiveness.
- Variability in key data points over time indicates potential issues with data representation.
- Exercise caution when interpreting and generalizing findings from traffic safety studies using the GES database.
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