Key research task activities included: (1) conducting a workshop with National experts on CRS misuse, injury prevention, and crash data to develop appropriate critical misuse measures; (2) selecting State sites and State site coordinators (SSCs) in six States; (3) holding a train-the-trainer workshop with SSCs and their field site managers (FSMs) to finalize CRS misuse definitions and data collection instruments, and to discuss recruitment and training techniques; (4) conducting field observations; (5) conducting data entry and analysis; and (6) preparing the final report.

A workshop was held within five months of the project start date with leading medical, bioengineering, and injury prevention experts in the field. The workshop included discussions on types of child injury severity in crashes; identification of the types of CRS misuse and their relationship to serious injury; and identification of the most important CRS misuse measures to include in data collection. Areas identified for critical CRS misuse measures in the workshop were: age and weight appropriateness of CRS; direction of CRS; placement of CRS in relation to air bags; installation of CRS to the vehicle seat; secureness/tightness of harness straps and crotch strap of the CRS; secureness/tightness of the vehicle safety belt (SB) to the CRS; locking clip use for vehicle SBs; fit of SBs across the children in belt-positioning booster seats; and damaged CRSs.

Six States (Arizona, Florida, Mississippi, Missouri, Pennsylvania, and Washington) were selected as data collection sites. States were selected based on their representing diverse geographic regions across the country; and encompassing diversity in socio-demographic and economic characteristics across field sites. The field sites included urban, suburban, and rural areas. It was critical for each State to have a qualified and experienced State Site Coordinator (SSC) who was familiar with managing field observations and could easily gain permission to conduct observations at sites in their area. State regional areas included Tucson (AZ); Boca Raton, Fort Myers, Fort Pierce, and Miami (FL); Jackson (MS); St. Louis (MO); Carlisle, and Harrisburg (PA); and Seattle and Tacoma (WA). Field observation sites were primarily parking areas at community shopping centers, child merchandise department stores, fast food restaurants, health and medical facilities, and community events.

A train-the-trainer workshop was held with SSCs and FSMs approximately one month before data collection to finalize CRS misuse definitions and data collection instruments. The workshop also covered recruitment of greeters and field observation staff; training techniques; data collection procedures; and project administration details.

Most sites conducted recruitment and training of staff in September 2002. It was required that all field observers be AAA certified CPS technicians. Data were collected from late September 2002 to early January 2003. Most of the States completed their data collection efforts by mid-November 2002. Project staff checked quality of data on a daily basis for the first two weeks and then weekly. Data entry and analysis were then conducted. A summary of the results was presented to NHTSA before the completion of the draft final report.

RESULTS

A total of 4,126 vehicles and 5,527 children weighing less than the driver-estimated weight of 80 lb were included in the study. There were 511 children weighing less than 20 lb; 2,483 children weighing 20 to 39 lb; and 2,533 children weighing 40 to 79 lb. By age category there were 676 children less than 1 year of age; 2,021 children from the ages of 1 through 3; 2,571 children from ages 4 through 8; and 259 children ages 9 and older.

For the total sample of children weighing less than 80 lb, 62.3 percent were restrained in CRSs, 25.9 percent were restrained in SBs, and 11.8 percent were unrestrained. CRS use by weight classification was as follows: 97.1 percent for children weighing less than 20 lb; 86.4 percent for children weighing 20 to 39 lb; 41.7 percent for children weighing 40 to 59 lb; and 10.9 percent for children weighing 60 to 79 lb. Safety belt (SB) use increased markedly for children 40 lb and over. SB use was 43.1 percent for children weighing 40 to 59 lb; and 64.9 percent for children weighing 60 to 79 lb. By age category, CRS use was 97.3 percent for children younger than 1 year, 90 percent for children ages 1 through 3, 37.2 percent for children ages 4 through 8, and 3.1 percent for children ages 9 and older. SB use increased markedly for children 4 through 8 years of age to 45.5 percent.

One or more critical misuses were found in 72.6 percent of all CRSs observed. Percentages of CRSs with critical misuses by seat type were as follows: infant (83.9 percent); rear-facing convertible (83.5 percent); forward-facing convertible (81.9 percent); forward-facing only (79.3 percent); belt-positioning booster (39.5 percent); and shield booster (60.5 percent).

The most common critical misuses were loose harness straps securing the child to the CRS and loose SB securing the CRS to the vehicle. Harness retainer clip misuse was also prevalent, but not deemed as a critical misuse in this study.

Other CRS misuse problem areas were also observed. They included visible damage to the CRS (e.g., cracked seat shell, torn harness strap, broken harness parts); percent of CRS base (bottom of seat) contacting the vehicle seat; and presence of aftermarket devices.

Forty-two observations of LATCH (Lower Anchors and Tethers for CHildren) were noted. Field observers found three seats with improperly used lower anchors, and three seats with improperly used tethers. Six seats were observed with both a safety belt and the lower anchors in use.

Children being transported by drivers who are restrained in SBs are more likely to be restrained than children who are being transported by unrestrained drivers. Of the observed drivers, 77.4 percent were restrained. When drivers were wearing a SB, 91.7 percent of children were restrained in either a CRS (44.2 percent) or SB (47.5 percent). When drivers were not restrained, only 62.3 percent of children were restrained in either a CRS (43.2 percent) or SB (19.1 percent).

Air bag systems were also observed. Driver frontal air bags were noted in 83.1 percent of the vehicles; passenger frontal air bags were found in 71.8 percent of the vehicles. Side air bags protecting passengers in the front seat were observed in 4.6 percent of the vehicles, and side air bags protecting passengers in both the front and rear seats were observed in 1.3 percent of the vehicles. Only a small percentage of the vehicles (less than 5 percent) had on/off air bag switches. For 88 vehicles checked for status of this on/off switch, 51vehicles had the switch “on” and 37 had the switch “off.” Sixteen children were in the front passenger seat with an activated (“on”) air bag switch; 2 of these children were in a rear-facing CRS, 4 were in a forward-facing seat, 3 were in a SB, and 7 were unrestrained.

RECOMMENDATIONS

Periodic monitoring of CRS misuse among the general public is recommended because of continuous upgrades and design changes to vehicle occupant protection systems and CRS models (e.g., LATCH systems, side air bags); frequent changes (strengthening) of occupant protection laws in States; and a perpetual supply of new parents responsible for protecting child passengers in vehicles. CRS misuse observations with the general public should be made by qualified and experienced personnel who are trained to gather CRS misuse data. Train-the-trainer workshops for supervisors, field managers and senior field observers prepare staff for field observations. At least two full days should be spent training field observers.

Continued enforcement of CPS laws is recommended, and there is general public acceptance for the enforcement of these laws. Programs need to be developed to make law enforcement agencies aware of the importance of correct CRS use, as well as keeping children in CRSs for as long as possible. Enforcement strategies need to be developed to identify booster seat law violations. Law enforcement should also continue to take an active role in community-based CRS education programs.

Education programs should continue to promote proper use of CRSs, enforcement of laws, availability of CRS inspection stations, loaner programs, and local and National CRS hotline information assistance. Programs should also provide information about LATCH systems and correct usage of the LATCH system.