Evidence that seat belts are as effective as child safety seats in preventing death for children aged two and up

"Over the last thirty years, the use of child safety seats in motor vehicles has increased dramatically, fueled by well publicized information campaigns and legal mandates. In spite of this movement, there is relatively little empirical evidence regarding the efficacy of child safety seats relative to the much cheaper alternative of traditional seat belts. Using data from the Fatality Analysis Reporting System (FARS) on all fatal crashes in the United States from 1975-2003, I find that child safety seats, in actual practice, are no better than seat belts at reducing fatalities among children aged 2-6. This result is robust to a wide range of sensitivity analyses, including controlling for sample selection that arises because the FARS data set includes only crashes in which at least one fatality occurs"--National Bureau of Economic Research web site.