A pair of recent international developments has focused attention once again on the issue of child restraints.
The British Medical Journal has come out with a recommendation that children should remain in rear-facing car seats until the age of four years. Meanwhile, the Washington-based Insurance Institute for Highway Safety has published ratings of child booster seats - those that fared well and those not recommended.
The report will obviously create discussion and concern about the ability of keeping children in a rear-facing seat based on age rather than the broadly accepted basis of weight or size.
One manufacturer, Dorel Industries Inc., which claims to be the world's biggest manufacturer of nursery and children's products, says that while there are pure safety arguments for the benefit of travelling in a rear-facing seat in the event of an accident, it is impractical after a certain point.
"We recommend parents to keep their child in rear-facing infant carriers for as long as possible and not to switch to a more convenient forward-facing seat at the earliest opportunity," the company says. But it also says the most effective way to improve child safety in car seats is "to ensure that the child is correctly fitted into the seat and the seat is correctly fitted into the car."
In the meantime, Dorel-made booster seats did not fare well in the IIHS report. The company markets its products under a number of names, including Safety 1st, COSCO, Maxi-Cosi and Quinny. It also supplies seats to Eddie Bauer Holdings Inc. Some of these are not recommended by the IIHS, but some are listed as good bets.
The IIHS tests should be of interest to parents because they are the first of their kind and the agency says the subsequent ratings range from those that performed well - "best bets" - to those that are "not recommended" based on the ability of the seat to correctly position the vehicle's lap and shoulder belt.
The IIHS says that unlike child seats and restraints designed for younger children - with internal harnesses, materials and structures to restrain the child, and absorb crash energy - "booster seats function as a positioning device to correctly place the child within the vehicle's seatbelt system."
With a booster seat, it is the vehicle's belt system that does the critical job of restraint by positioning those belts across the stronger bony structures of the hip and clavicle/collar bone, rather than across the softer tissue of the abdomen and neck.
Scientists and engineers at the University of Michigan Transportation Research Institute, working with the IIHS, measured how lap and shoulder belts in 41 booster seats fit a test dummy representing the average size and weight of a six-year-old.
"Though seatbelts are highly effective at reducing injury in a crash, those that are incorrectly positioned across the lap have the potential to cause injury to the abdomen if positioned too high and if they allow children to slide under them during a crash.
"Shoulder belts positioned too closely to the neck do not place the load ideally over the clavicle/collar bone, but are also uncomfortable, which may cause children to hold the belt away from their neck or put the shoulder portion of the belt behind them, reducing the belt's protection," the report says.
Details of the ratings and how they were arrived at can be found at http://www.IIHS.org.
Consumer Reports magazine says the new IIHS test results are an important part of the overall picture. But, like Dorel, it says practical issues should also be considered.
It evaluates how easy the seats are to use, how they fit in vehicles and how they perform in a series of simulated crash scenarios. It says seats that rate well in its tests and are also rated "good" or "best bets" by the IIHS study are obviously a wise choice.
But before you throw away a perfectly good booster seat, Consumer Reports also says that if you own a seat that falls into the IIHS "not recommended" category, "it's more important to perform your own assessment of fit with your own child and car."
Consumer Reports says that while the dummy used in the IIHS tests represented the "average" six year-old, children come in a wide variety of shapes and sizes. It recommends parents and caregivers assess children, seats and vehicles for proper fit as follows:
Does the booster seat position the shoulder belt across the clavicle/collar bone, approximately midway between the neck and shoulder?
Does the booster seat position the lap belt low across the hips/top of the thighs?
Does either the booster seat or vehicle head restraint provide some support behind the child's head?
Is your child comfortable and not tempted to move the belts or themselves out of position after a period of time?
Halifax-based Richard Russell runs a driving school.