Since 1970 an extensive research program has been in progress within the United States to identify appropriate criterion levels for minimum braking and handling performance of passenger cars. The predominant methodology has been oriented toward skid pad performance measures on the assumption that vehicles that perform well in skid pad maneuvers will have fewer accidents than poor performers. This approach has been adopted because accident reporting and investigation procedures have not been structured in a way that would permit positive identification of the role of vehicle handling factors in accident causation.

When indirect measures of safety performance are used, vehicle design should be evaluated in context with other elements of the driver-highway system that influence braking and handling qualities. A pilot study was conducted using indirect measures of safety performance. The results indicated that tire-pavement traction is the dominant factor in vehicle braking performance on public roads. This finding is consistent with other published evidence that small differences in pavement friction levels produce detectable differences in accident rates. It is concluded that accident data sensitive enough to detect such effects should also be sensitive enough to detect differences in accident ratcs produced by vehicle cornering and braking capabiilities.