Is there any evidence head restraint improvements

Is there any evidence head restraint improvements are effective in reducing neck injuries?

Recently the Institute gathered data from Nationwide, Progressive, and State Farm insurance companies to look at improved seat design in rear-end crashes. More than 2,000 property damage liability claims were identified involving selected vehicles. The vehicles studied were the Ford Taurus and Mercury Sable models with improved head restraint geometry, Volvo S70s with WHIPS (Whiplash Injury Prevention System), Toyota and Lexus models with the WIL (Whiplash Injury Lessening) system plus a number of Buick, Nissan, Pontiac, and Saab models with active head restraints. The rates of insurance claims for driver neck injuries in the rear-end crashes were compared before and after the seat and head restraint design changes. A 43 percent reduction in neck injury claim rates was seen for the Saab, General Motors, and Nissan models with active head restraints, compared with similar cars before such restraints were introduced. Similar before/after comparisons of Volvos and Fords showed reductions in claim rates. A 49 percent reduction was seen in Volvos compared with an 18 percent reduction in the Fords with improved geometry. The Toyota WIL system did not show any reduction in neck injuries.¹⁵

¹⁵Farmer, C.M.; Wells, J.K.; and Lund, A.K. 2003. Effects of head restraint and seat redesign on neck injury risk in rear-end crashes. Traffic Injury Prevention 4: 83-90.