II. Trends in Occupant Restraint Use
and Fatalities

The National Picture

Buckle Up America is based on the premise that boosting the occupant protection use is the single most effective strategy that can save lives and reduce injuries on American roadways, and increasing the national occupant restraint use rate is at the heart of the program. The four principal components to BUA, building partnerships, enacting new legislation, conducting strong enforcement, and expanding public information & education, were specifically designed to lead to a higher occupant protection use rate, that a goal of 90 percent nationwide belt use would be reached by 2005, and that higher occupant restraint use would, consequently, contribute to fewer occupant fatalities. Occupant restraint use is one of two "bottom line" outcome measures used to evaluate BUA. The other is the number of occupant fatalities, in particular, child fatalities. Both outcome measures are discussed in this chapter, beginning with occupant restraint use.

Occupant Restraint Use

Three widely known, independent measures of occupant restraint use are discussed below. The three are: 1) the National Occupant Protection Use Survey; 2) state reported belt use rates; 3) and the Motor Vehicle Occupant Safety Survey.

National Occupant Protection Use Survey (NOPUS)

NOPUS provides detailed information on overall shoulder belt use for drivers and right-front seat passengers. Begun in 1994, NOPUS was repeated in 1996, 1998 and 2000. It is an extensive effort for which data collection occurs at over 3,800 sites across the country. Figure 1 shows that the 2000 NOPUS measured the overall observed seat belt use rate at 71 percent, compared to 69 percent observed in 1998, 61 percent observed in 1996 and 58 percent observed in 1994. These estimates reflect statistically significant changes (NHTSA, 2000a). 

Figure 1.
National Occupant Protection Use Survey
Front Seat Belt Use Rate
d

The 1996 and 1998 NOPUS also provided detailed information on child restraint use for children under five-years of age. Figure 2 shows that tremendous gains were achieved in only two years. This was especially true for children one to four years old. The figure also shows that usage rates were lower as the age of children increase (NHTSA, 2000a).

Figure 2
National Occupant Protection Use Survey
Children <5 Years
d

State Reported Seat Belt Use Rates

All fifty states, the District of Columbia, and Puerto Rico are required by NHTSA to conduct annual, scientific surveys of driver and front seat passenger belt use. Each year, NHTSA collects the state data and weights it to reflect a national belt use rate. Figure 3 shows the weighted national belt use rates for 1988 through 1999. Belt use increases were largest in the first half of the decade. The most recent result, for 1999, was the highest ever (70%) (NHTSA, 1998, 1999).

Figure 3
Weighted National Seat Belt Use Rate;
State Reported, 1988-99
d

Contrary to NOPUS, statewide survey results indicate little increase in the belt use rate from 1994 to 1998.

Primary law states, as a group, have always out-performed secondary law states. The graph in Figure 4 provides a snapshot of this fact using 1998 data, as reported by states (NHTSA, 1999). The belt use rate, averaged across primary law states, was 14 percentage points higher than across secondary law states. Belt use was above 85 percent in only one state (CA) and at or above 80 percent in four additional states (MD, NM, OR, HI) and the District of Columbia, and primary, or standard enforcement is allowed in all of these places.

Figure 4
State Reported Seat Belt Use Rates, 1998
d

Two states, Maryland and Oklahoma, and the District of Columbia upgraded their seat belt laws from secondary to primary enforcement in 1997. Seat belt use rates in each of these locations made small gains, if any, from 1993 through 1997 (Table 1). Then, immediately after the law change, belt use rates increased. The increases ranged from +9 to +14 percentage points. The national belt use rate changed only moderately from 1993 through 1997, remained unchanged from 1997 to 1998, then decreased in 1999. The increases measured in the new primary law locations were similar to increases seen in three other states that changed from a secondary to a primary law earlier in the 1990s: California (+18 percentage points); Louisiana (+16 points); and Georgia (+5 to 10 points) (Ulmer et al., 1995; Preusser and Preusser, 1997; Ulmer et al., in process; Solomon et al., 2001). Three more states, Alabama, Michigan, and New Jersey, more recently upgraded to a primary law, and effects of the change have yet to be measured.

Motor Vehicle Occupant Safety Survey (MVOSS)

MVOSS, begun in 1994, is a biennial telephone survey conducted for NHTSA. For each MVOSS, nearly 8,000 randomly selected Americans, age 16 and older, are questioned on attitudes, beliefs, and behaviors concerning occupant protection. Program areas include seat belts, child safety seats, air bags and other areas related to protecting motor vehicle occupants. Table 2 provides results on a number of occupant restraint topics. MVOSS (Table 2) found an upward trend in self-reported occupant restraint use, especially child restraint use. Increasingly favorable attitudes toward occupant restraint laws and enforcement were also evident. The latest MVOSS results (1998) showed that an overwhelming majority favored a seat belt law for front seat occupants (86%). A smaller majority showed support for a primary law (58%); respondents in primary law states, more than respondents in secondary law states, supported standard enforcement (68% versus 50%). Nearly everyone supported a child restraint law (94%), and over half (60%) believed police should always cite child restraint violations (NHTSA, 2000b).

Fatalities

The Fatality Analysis Reporting System (FARS) is a census of fatal crashes within the 50 states and the District of Columbia. From 1998 FARS data and Federal Highway Administration estimates of miles driven, fatalities per 100 million vehicle miles of travel were calculated (Figure 5). In 1998, the fatality rate remained at its historic low of 1.6, the same as in 1997, and down from 1.7, the rate from 1992 to 1996 (Traffic Safety Facts, 1997, 1998, 1999, 2000). 

Over time, as the belt use rate improved, fatalities (per 100 million miles traveled) also decreased (Figure 5). Both higher use rates and lower fatality rates improved dramatically in the early 1990s. An additional improvement, but not as dramatic, was noticeable after 1996.

Figure 5
Seat Belt Use Rate and Fatalities
per 100 million VMT, 1988-98
d

Child Fatalities

There are dozens of child safety seat models and hundreds of passenger vehicle models, and it is being recognized increasingly that their proper use is complex and difficult to achieve. A new initiative requiring universal three-point mounts in all vehicles beginning with the 2002 model year and child safety seats designed to use those mounts, was announced in early 1999. Until then, the goal has been for caregivers to obtain child safety seats which are compatible with their vehicles, learn how to properly use the child safety seats, and always use them properly.

NHTSA and partnered organizations developed programs to increase protection of the nation's youngest passengers. A couple of notable programs should be mentioned. Operation ABC Mobilizations targeting child passenger safety were highly visible and brought coverage to nearly all of the U.S. During National Child Passenger Safety Week, communities and advocates in every state were urged to carry out activities that promote seat belt and child restraint use along with bike and pedestrian safe behavior.

Table 3 shows recent child fatality data (FARS). The number of children under age one killed in crashes dropped from 1996 to 1998 (20.9%), as did the number of children ages one to four (8.6%). A smaller number of children killed were unrestrained and fewer in safety seats were killed (Traffic Safety Facts, 1997, 1998, 1999, 2000). The fatality data support the conclusion that more kids were buckled up and that more parents are buckling up their children properly.

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