Installing car seats improperly can be just as dangerous as not placing children in car seats at all.

Last year, the Centers For Disease Control and Protection (CDC) said that motor vehicle accidents were the leading cause of death among children in the U.S.

Later, the National Highway Traffic Safety Administration (NHTSA) countered that statement with its own, saying that the deaths could have been prevented if the children had been traveling in age-appropriate and size-appropriate restraint systems.

The NHTSA also noted that of all the children who were killed in motor vehicle accidents, almost half were unrestrained. However, even when children were placed in restraint systems, it didn’t insure their safety. That’s because, of the 3,500 child restraint systems used, 72 percent were used improperly, according to the NHTSA.

The restraint system that seems to be the most difficult for parents to use correctly is the car seat. Some seats are cumbersome and come with multiple harnesses that have to be installed by reading a lengthy instruction booklet. Some parents complain that it can take a frustration-filled hour or more to get a seat into place.

In fact, this frustration may be the biggest reason for some of the mistakes parents make when installing car seats, such as:

— Ignoring the manufacturer's instructions for installation. Many parents decide to chuck the instruction book and instead try to figure out how to install the seat on their own.

— Forgetting to read their car owner's manual to determine the safest place to install the seat in the car. If they don’t find any placement recommendations or if the instructions aren’t clear, parents often fail to call the car seat manufacturer to get the company’s recommendation as to where to put the seat.

— Not installing the car seat so that it faces the rear of the car when it is being used for a child under a year old. Most experts recommend that it remain facing the rear until the child is 18 months old.

— Installing the seat too loosely. There should be no wiggle room after the seat is in place. The seat shouldn’t be able to move more than one inch forward or sideways. Seat belts need to be pulled as tightly as possible so that the seat is kept as immobile as possible.

— Leaving the harness straps too loose. Straps should fit snuggly around the child. The harness retainer clip, which snaps the vertical and horizontal straps together, should be at the same levels as the child’s armpits. It is often placed on the same level as the child's belly. That's too low to provide the proper restraint in an accident.

— Failing to use all of the harnesses to secure the child into position. There are two types of car seats, those with a 3-point harness systen and those with a 5-point harness system.A 3-point harness system has two straps at the shoulder and one between the legs. A 5-point system has two straps at the shoulder, two at the hips, and one between the legs.

Dr. Jan Shook, medical director of the Emergency Department at Texas Children’s Hospital, agrees that children are often injured due to improperly installed car seats.

Shook said the high number of incidents occur because people are not adhering to stabilization guidelines. She has seen children suffer from fractures, lacerations, and head injuries as a result of not being immobilized in a car seat. She also noted that, in extreme instances, children have been propelled from the vehicle because parents failed to secure them in the seats correctly.

The federal government, in an effort to simplify the installation of child restraints without using seatbelts, developed the LATCH system. LATCH is an acronym for lower anchors and tethers for children. A child safety seat that uses the LATCH method attaches to anchors in the back seat where the cushions meet. A strap called a tether connects the top of the safety seat to the car's frame. All child safety seats and vehicles made after September 2002 must come with LATCH.

Even with the LATCH system, some parents still have difficulties. The American Academy of Pediatrics recommends contacting a certified Child Passenger Safety (CPS) Technician for help. To find a child safety seat inspection station and set up an appointment, call 1-866-SEATCHECK (1-866-732-8243) or log on to www.seatcheck.org.

Ranking of all of the car seats tested can be found by logging on to www.healthycar.org.