Seat Belts and Child Restraints
Overview
Abundant research has shown that correctly using an appropriate child restraint or seat belt is the single most effective way to save lives and reduce injuries in crashes. Lap and shoulder combination seat belts, when used, reduce the risk of fatal injury to front-seat passenger car occupants by 45% and the risk of moderate-to-critical injury by 50% (Kahane, 2015). For light-truck occupants, seat belts reduce the risk of fatal injury by 60% and moderate-to-critical injury by 65%.
NHTSA estimates that correctly used child restraints reduce fatalities by 71% for infants younger than 1 year old and by 54% for children 1 to 4 years old in passenger cars. In light trucks the fatality reductions are 58% for infants and 59% for children 1 to 4 years old (Kahane, 2015; National Center for Statistics and Analysis [NCSA], 1996;). In addition, research conducted by the Partners for Child Passenger Safety Program at the Children’s Hospital of Philadelphia found that belt-positioning booster seats reduce the risk of injury to children 4 to 8 years in crashes by 45% when compared to the effectiveness of seat belts alone (Arbogast et al., 2009). However, unrestrained children continue to be overrepresented in motor vehicle fatalities, which indicates that additional lives can be saved by increasing restraint use among children (Sauber-Schatz et al., 2014).
All new passenger cars had some form of seat belts beginning with lap belts in 1964, shoulder belts in 1968, and integrated lap and shoulder belts in 1974 (Automobile Coalition for Traffic Safety [ACTS], 2001). New York enacted the first statewide seat belt use law in 1984 with other States soon following. As of August 2020 all States except New Hampshire required adult passenger vehicle drivers and front-seat occupants to wear seat belts and 30 States and the District of Columbia also required seat belts for all rear-seat passengers (GHSA, 2020). From 1978 to 1985 every State and the District of Columbia passed laws requiring child restraints for young child passengers (Kahane, 1986), and most of these laws have since been amended and strengthened to include more children and to close loopholes and exemptions. Still, great variation exists on the requirements and ages covered by State child restraint laws.
Despite the demonstrated effectiveness of seat belts and child restraints and laws requiring their use, challenges remain. Current data show that observed daytime seat belt use nationwide was 91.6% in 2022 for adult drivers and right-front seat passengers combined (NCSA, 2023a). In 2021 seat belt use was over 90% in 23 States, the District of Columbia, and 3 U.S. Territories, with California (97.2%), the District of Columbia (95.9%) and the Northern Mariana Islands (96.4%) achieving belt use rates higher than 95% (NCSA, 2021c). Seat belt use, however, was less than 80% in Massachusetts (77.5%), New Hampshire (75.5%), and the U.S. Virgin Islands, (72.3%) (NCSA, 2022a). Nationally, seat belt use has increased dramatically since seat belt use laws went into effect in the early 1980s (Hedlund et al., 2008; NCSA, 2023a). The national seat belt use rate has been trending upwards over the past 2 decades, rising 21 percentage points since 2000 (NCSA, 2007, 2023a).
U.S. Driver and Front Seat Passenger Seat Belt Use Rates: 2000 – 2022
Sources: NCSA, 2007, 2023a
However, the national seat belt use rate is for daytime seat belt use. Research has found seat belt use to be lower at night. In 2021 some 57% of passenger vehicle occupants killed in crashes at nighttime were unrestrained. In contrast, 43% of fatally injured passenger vehicle occupants in daytime crashes were unrestrained (NCSA, 2023c).
Historically, overall restraint use for children was higher than what was demonstrated in the adult population. More recently, the rates have become similar. In 2021 restraint use for children younger than 13 was 89.8% (Boyle 2023). Restraint use ranged from 99.8% for infants under 1 year old, to 86.8% for children 8 to 12. In general, child restraint usage rates decline as children age.
Restraint Use Rates for Children* by Age, 2021
Source: Boyle, 2023 (*Restraint use rates do not indicate correct use.)
However, restraint use for children is more complicated than simply “restrained versus unrestrained.” In addition to overall restraint use, it is also important to consider correct restraint use. NHTSA and the American Academy of Pediatrics have recommendations for restraining children based on their age and size (AAP, 2021; Durbin et al., 2018; NHTSA, 2019).
Looking more specifically at appropriate restraint use, the 2021 National Survey of the Use of Booster Seats (NSUBS) shows indications of premature transition to restraint types that are not appropriate for children’s ages, heights, and weights (Boyle, 2023). In 2021 some 91.8% of children under age 1 were observed in the appropriate rear-facing seats, essentially unchanged from 91.7% in 2019. Rear-facing and eventually forward-facing car seats are appropriate for children 1 to 3. The 2021 NSUBS found that 86.8% of children 1 to 3 used the appropriate restraint, compared to 83.7% in 2019, and 73.2% of children 4 to 7 were restrained using the appropriate forward-facing car seat or booster seat, which is up slightly from 69.0% in 2019. Of children 8 to 12, 85.8% were appropriately restrained, up slightly from 85.0% in 2019. Children 8 to 12 should use booster seats until the seat belt fits properly.
Despite high observed belt use rates, many unrestrained people die in crashes each year. In 2021 half (50%) of the 26,325 fatally injured passenger vehicle occupants with known restraint use were unrestrained (NCSA, 2023b). Of the 863 children under 15 who died in passenger vehicles in 2021 some 40% were unrestrained (NCSA, 2023b).