Pursuant to a congressional request, GAO evaluated studies on safety belt laws, focusing on: (1) safety belts' effectiveness in reducing fatalities and severe injuries; (2) the effectiveness of safety belt mandatory use laws; and (3) the societal costs incurred when people who do not wear safety belts are involved in accidents. GAO found that: (1) 21 safety belt effectiveness studies comparing death and serious injuries experienced by belted occupants with unbelted occupants show that belt use reduces both the fatality rate and the serious injury rate by 50 to 75 percent in motor vehicle accidents; (2) although the studies vary in methodologies used and data source approaches, 13 studies that specifically analyzed occupant deaths showed that the fatality rates for belted occupants ranged from 41 to 94 percent lower than the rates for unbelted occupants; (3) 11 studies comparing injuries received by belted and unbelted occupants show that injury levels for belted occupants range from 17 to 88 percent lower than the rates for unbelted occupants; (4) 22 studies evaluating the effectiveness of mandatory safety belt use laws show that state laws have been effective overall in preventing deaths and reducing injuries; (5) 17 studies show that laws requiring safety belt use reduce fatality rates by 5 to 20 percent, while 14 additional studies also show that most injury reductions range from 5 to 20 percent; (6) many existing state laws mandating safety belt use could be strengthened by including coverage to rear seat occupants, extending coverage to light trucks and vans, and facilitating fines for not using safety belts; (7) a May 1991 report sponsored by the Federal Highway Administration estimate the total 1988 annual costs of traffic accidents to be $334 billion; (8) studies show that hospital costs for belted victims are 60 to 80 percent lower than hospital costs for unbelted victims; and (9) one study suggests that society pays up to 69 percent of out-of-pocket costs | Highway Safety by U U S Government Accountability Office (G, Paperback | Indigo Chapters