Statewide surveys vary in methodology and frequency of observation.
However, all except Wyoming are based upon direct observation of safety belt use. Because the surveys are generally based on a large number of observations from representative sites, they provide a reasonable estimate of seat belt use. For the moving traffic study, which provides information on overall shoulder belt use, pairs of observers were stationed for 30 minutes at exit ramps, intersections with stop signs or stop lights and uncontrolled intersections. The second observer counted belt use for the right front passengers. Every day of the week and all daylight hours were covered by the study.