National Occupant Protection Use Survey
The National Occupant Protection Use Survey (NOPUS) is the only nationwide probability-based observational survey of seat belt use in the U.S. The survey observes usage as it actually occurs at a random selection of roadway sites, and also provides the best tracking of the extent to which vehicle occupants in this country are buckling up.
Seat Belt Use in Rear Seats in 2008. Traffic Safety Facts Research Notes. National Highway Traffic Safety Administration, 2009. Available at: http://www-nrd.nhtsa.dot.gov/Pubs/811133.PDF