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Someone here clearly has a problem differentiating "needs" from "wants". Four carseats FFS: is that even a reasonable 'want'?
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Florence Kelly's profile photoAdnan Sadzak's profile photoandrew mcmillan's profile photoPeter Kelly's profile photo
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Read Freakonomics and you'll hear that car seats offer very little value in actual increased safety. It's playing in the fears of anxious parents for profit. Especially our ridiculous car restraint mount point laws. The cost quoted on car seats by this guy seemed low to me. Maybe he rented a few before finding one that worked for them.
 
It'd be nice to have a link to whatever that statement is based on. I can't easily find anything on the internet that says "children's car seats offer little additional safety" but I can see people being prosecuted for manslaughter for not putting their child into one. That would seem like a harsh response, and if there is little evidence for the benefit the weaselling out of such charges would hopefully be easy.

Our kids were each in a rented baby capsules for their first six months, then moved into a forward facing full harness baby seat for several years before moving into booster seats until they were 130cm. The booster seats really did mean that the seatbelts (which surely nobody still argues don't save lives) now fit much better, but also that they had the height to see out the windows.
 
Andrew, I think that either Stephen Judd or I have a copy somewhere.
 
Or even my local library - not that they're open today. What I find odd, is that the assertion that "child carseats don't improve safety" doesn't seem to be something I can find examined either for or against very easily. Maybe my google-fu is not up to the task :-)
 
Also, check Amazon to make sure that they have the same name in American.
 
"children's car seats offer little additional safety"? Clearly that statement is nonsense. One need only talk to people in paediatric intensive care to know better. Children's car seats provide additional safety in many ways. Firstly, when rear-facing, they provide extra protection to children's weak and vulnerable necks in a crash. Secondly, try putting a baby in a normal adult seat-belt. It just won't work. The early stage car seats have a 5-point harness, making it harder for children to slip out of and holding them more securely. Another way people might think of having kids in the lap or sharing an adult seatbelt also won't work. Either kids would be cut in half by the force of the adult squishing them into the seatbelt, or the adult has no hope of holding onto the child in a crash. Next point, the tether strap, which is attached to an anchor point in the car, holds the car seat in place to stop it rocking and also provides extra safety on top of the seatbelt - which also holds the car seat in place. Occasionally one hears in the media of terrible crashes where the baby is the only one unhurt, and they credit the car seat. Naturally there may be confounding factors - e.g. the child is in the centre of the car, the safest place.
 
+andrew mcmillan - the content is in an actual published book, not an article on the internet - see references below. They do have a blog at http://freakonomics.com which may have more.

+Florence Kelly My point is that we are forced by law to restrain children in expensive "child safety seats" (in Victoria up to 7 years of age) even when for these older children there is no evidence to support the notion that these products provide any additional benefits in safety over the cars standard safety equipment.


No-ones talking about babies - the article referred to is a lifetime analysis. Also additional safety means over and above that supplied by a legal vehicle, that is the cars standard seat-belts, air-bags and so on. So the babies in laps is a straw-man.

The figures quoted in my references are NHTSA accident statistics (USA) and are very comprehensive. They show that for children 2 years of age or over the rates of fatality prevention are no different for seat belts versus child seats. For collisions where a vehicle is impacted from the rear the child seats do slightly worse.

pp138-139 Freakonomics, c2005, Steven D Levitt & Stephen J Dubner; pp 150-158 SuperFreakonomics c2009 by Steven D Levitt & Stephen J Dubner.

Clearly its nonsense? How exactly? There are plenty of products which claim to provide a benefit, but which actually do no more than cheaper options.

What's more product manufacturers love it when their products are mandated into law.

For babies an infant car seat is the best, and the Dubner & Levitt figures show good results for those seats up to age 2 years. Victorian law seems to mandate baby capsules only up to one year of age after that allowing seat-belts: http://www.vicroads.vic.gov.au/Home/SafetyAndRules/SaferVehicles/BuyingASafeCar/SeatBelts.htm
Laws vary from state to state with some providing penalties for not using child restraints until the child is 7 years of age. Drivers who have children in seat-belts are liable under the law, even though the evidence presented by Dubner & Levitt shows that there is no proven additional safety.

What if I come up with a "child safety garden hose" with the professed goal of averting the risk of children strangling or drowning themselves with conventional hoses in peoples back yards - and charge 3 times as much for it? Anyone that objects gets shouted down with "will no-one think of the children" and next thing you know my product is mandated into law.

That's fine if there really is a proven benefit, as there is for example with pool fencing. As Dubner & Levitt argue, if your child has a choice to go play at a house A where the parents have a pool and house B where the parents have a firearm (all standards of precautions for those two dangerous items being equal) you are much safer on the statistics allowing the child to play at the place with the firearm. Pools are so dangerous. This is not a "pro-gun" position - its just the numbers.

But we should be looking at the numbers here and not allowing emotive ploys by manufacturers to get us using their products long after they're necessary. Car crashes, like guns are violent and scary - thus they can be used to scare us into approving laws mandating products that make us feel safer, without really providing any additional safety benefit. Certainly we should resist the use of legislation to improve profits.

Maybe there are other benefits apart from actual safety to child restraints such as the ability to secure the child in such a way that he or she cannot wriggle out at all. Also having a child seat might provide a memory-jogger to the parent into the fact that special care is needed to ensure the child is actually properly in a seatbelt (and not on a lap).

But once the child is in a seat belt, or child seat, they're on an equal footing safety wise, on these numbers. So why is there a law to force us to spend extra money on these things?
 
http://scholar.google.co.nz/scholar?hl=en&q=%22child+restraint%22+&btnG=Search&as_sdt=0%2C5&as_ylo=&as_vis=0 seems to be a route into some further data. Freakonomics is great fun, but it is no substitute for looking at the peer-reviewed literature.

From "Recent Trends in Child Restraint Practices in the United States":

"BPBs reduce the risk of head and brain injuries, all internal organ injuries, spinal cord injuries, and extremity fractures by 59% when compared with seat belt restraint in 4- to 7-year-old children.5 In particular, BPBs virtually eliminated seat belt syndrome in these children; that is, injuries to the abdominal organs and lumbar spine and spinal cord." [5 Durbin DR, Elliott M, Winston FK. Belt-positioning booster seats and reduction in risk of injury among children in vehicle crashes. JAMA.2003;289 :2835– 2840]
 
And another one - one of the first studies on the subject, with over 200 citations: "Conclusions. Premature graduation of young children from CRS to seat belts puts them at greatly increased risk of injury in crashes. A major benefit of CRS is a reduction in head injuries, potentially attributable to a reduction in the amount of head excursion in a crash." Winston et. al., PEDIATRICS Vol. 105 No. 6 June 1, 2000
pp. 1179 -1183
 
"Expensive"? Victoria must be seriously out of whack with the rest of the world then. Here in New Zealand we only need to use a booster seat for Max from when he was around 3 or 3 and a half. Fraser might have stayed in the child seat a little longer, but not too much.

The booster seats we used after that are simple fabric-covered molded polystyrene designed to position a child so that the in-car seatbelts are in a more suitable location. We kept Fraser in his until after he turned 11.

Car safety features are obviously very badly designed for smaller children, but parents also probably do tend to move from a rear-facing seat to a forward facing seat too young. I think that in New Zealand most capsule seats for the very young are rented from Plunket for a nominal fee.

Other than the obvious safety issues, part of the problem that is being addressed in a seat for under 5s is control: many three year olds would be capable of undoing a normal seatbelt and would think it a great lark to get mum screaming at them as she drove across the centreline. It was a relief to us to know that once they were in there, they stayed there, and we could get on with going where we needed to be.
 
+Peter Kelly Have you read SuperFreakonomics?

On page 246 in the references section Dubner & Levitt reference the Winston et al research specifically. They also reference a paper by Dr Levitt "Evidence that Seat Belts Are as Effective as Child Safety Seats in Preventing Death for Children" in The Review of Economics and Statistics 90, No 1 (Feb 2008), as well as several other papers. I think that is peer reviewed study.


Levitt's techniques are to analyse large quantities of hard data - he is not a doctor. But are paediatricians who are regularly having to treat children who are injured in vehicle collisions more unbiased?
They point out regarding the referenced studies that they are based on parent interviews. They say in part "If your child was riding unrestrained in a car crash, you might feel strong social pressure ... to say your child was restrained. The police report will show whether of not the vehicle had a car seat, so you can't readily lie about that. But every backseat has a seat belt, so even if your child wasn't wearing one, you could say he was and it would be difficult for anyone to prove otherwise"

Dubner and Levitt readily admit that restraints are right for children under two, and they further say that evidence shows reduction in minor injuries.

The Dubner & Levitt books are fun, but they're writing about the challenging results coming from serious research, which they refer to extensively. I don't agree with you that it is "no substitute" - these books are whilst themselves not serious research, they are very useful surveys of serious research, and like anything must be read with a critical eye.

The numbers they quote come from 30 years of data from the Fatality Analysis Reporting System, which goes back to 1975. This is very different to the reduction in injury focus of relatively recent and more advanced child seats referred to by Winston. Fatalities are not the subject of the studies by the paediatricians and other "concerned citizens".

Also in the later book SuperFreakonomics, Levitt commissioned his own side-by-side study in a crash-test lab. At the time Levitt noted the dearth of actual side-by-side comparison tests like this - in those tests which are similar to those used in verifying the compliance of child safety seats the sensor data showed that neither the seat-belt nor the child seat suffered injury. Levitt says that the paediatricians point out that the sensors on the crash-test dummies do not measure trauma to the neck, and thus are not able to measure some types of injury called "seat belt syndrome".
Modern child safety seats have multi-point restraints and are in some cases rear-ward facing. If you've flown internationally you'll know that this is exactly what flight attendants have as their seating. The reasoning of course is so that they survive and are able to assist in getting injured passengers out. But the point is a much higher standard of safety and restraint system is being applied to them.

If adults wore multi-point restraints, and had wrap around capsules that protected them, and also if these adults always travelled in the much safer back seat, (which is where the child safety seats happen to be located) then they too would likely enjoy these much increased rates of injury protection.
 
+Peter Kelly You're right - these books are no substitute for peer reviewed research. I over-stated my position there. :-)

But they cannot be simply dismissed either as they are more accessible, and they do back their claims with peer-reviewed research along with other literature surveys.
 
While I wasn't dismissing this research, I do think that it is wiser to make policy by looking at the consensus inside the medical field, rather than broad brush critiques from outside it. I hope and expect that these contrarian views will be taken seriously and their approaches will inform medical journals in time. I'm not saying the study is ludicrous; way up at the top of the thread Andrew said it wasn't easy to find for and against, and we've now provided some.

It also takes time to 'prove' truths sometimes. What was the point in which experimentally and scientifically it become 'proven' that socialism was doomed cf. capitalism? Probably that standard has not been met - messy data - but you still be a silly dictator to nationalise the means of production, distribution, and exchange.
 
+Sarah Smith also note how much this sounds like the climate change 'debate': consensus in the relevant journals, attacks from right field in narrow sectoral journals on somewhat orthogonal issues... but I think you are on the conventional side of the clmate change issue :-P
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