May 7, 2008 -- The safest spot for a baby's car seat is in the center of the back seat rather than on the sides, according to a new study.

Although older passengers using seat belts can decide where they sit in a car, researchers point out that a child's seat is determined by where the child-restraint system is installed. For ease of access and keeping an eye on a baby, the most common spot for a baby's car seat is the rear passenger side.

But the study showed that children under age 3 seated in the center of the back seat had nearly half the risk of injury in motor vehicle crashes than children seated in either of the other positions.

"The center rear seating position is used less often by children restrained by a child-restraint system as they get older," writes researcher Michael J. Kallan, MS, University of Pennsylvania School of Medicine, and colleagues in Pediatrics. "Children seated in the center rear have a 43% lower risk of injury compared with children in a rear outboard position."

Researchers say current child restraint safety guidelines recommend the center position as long as a snug fit of the car seat can be achieved. But those recommendations are based on research that was conducted a decade ago.

Center Seat Safest for Children

In this study, researchers looked at whether those recommendations were still valid by analyzing data on child occupants of motor vehicle accidents from 1998 to 2006 based on insurance claims and a telephone survey.

The analysis included children from birth to age 3 who were seated in a child-restraint system in the rear seat of motor vehicles (model year 1990 or newer) that were involved in a crash in 16 states.

The results showed that the passenger side rear seat was the most popular position for the baby or child's car seat (41%) followed by the left (driver's side) rear seat (31%) and center seat (28%).

Researchers also found use of the center position decreased as the child got older. For example, 39% of baby car seats for infants under age 1 were placed in the center rear seat vs. 18% of child car seats for 3-year-olds, regardless of any additional passengers in the rear seat.

Children seated in the center had a 43% lower risk of injury than those in either side position, which researchers say revalidates current child-restraint safety recommendations.

"Although placement in any rear seating position provides excellent protection," write the researchers, "those in the center have the lowest risk of injury."

Researchers say recommendations should continue to encourage families to install child and baby car seats in the center of the rear seat.

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