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UlrikeDG
07-17-2007, 01:22 AM
I'm looking for the supposed studies from "Europe" which showed rear facing is unsafe past 25 lb. I found this instead:

Inertial Neck Injuries in Children Involved in Frontal Collisions (http://www.sae.org/technical/papers/2007-01-1170)Abstract:
There is a paucity of data regarding the potential for pediatric cervical spine injury as a result of acceleration of the head with no direct impact during automotive crashes. Sled tests were conducted using a 3-year-old anthropomorphic test device (ATD) to investigate the effect of restraint type and crash severity on the risk of pediatric inertial neck injury. At higher crash severities, the ATD restrained by only the vehicle three-point restraints sustained higher peak neck tension, peak neck extension and flexion moments, neck injury criterion (Nij) values, peak head accelerations, and HIC values compared to using a forward-facing child restraint system (CRS). The injury assessment reference values (IARVs) for peak tension and Nij were exceeded in all 48 and 64 kph delta-V tests using any restraint type. The test at a delta-V of 64 kph using only the vehicle belts as restraints resulted in peak upper neck tension, peak upper neck extension moment, and Nij values two times greater than the corresponding IARV. Only small differences were found in the injury metrics between a CRS installed with and without webbing tension except that head excursion was greater in the installation without webbing tension. These data show that the potential for neck injury exists for children involved in severe frontal crashes and restrained in either a forward-facing CRS or by vehicle belts¿only, even in the absence of head contact.

Can't find the full text elsewhere, and I'm not dishing out $14 to read it.

CRS
07-17-2007, 06:11 AM
Man I must have potty brain today, I don't understand what that's meant to be saying?

papooses
07-17-2007, 08:51 AM
Heh, I needed my coffee before I could focus on that ... I do miss the days before I became addicted to caffiene!

Focusing on the concluding sentence -- even if the child (over 2 years old, which is the cut off for Freakonomics theory) does not impact the vehicle interior there is increased risk of spinal injury when FF: basically, it's saying to keep kids RF (information based on U.S. autopsies only looked at kids under 24 months reveal that they're about 4 times as likely to suffer fatal spine injury when FF, but there wasn't enough kids still RF over 2 years old so this is a nice study to say basically that the *only* recommended time to turn FF is when the child can no longer fit the RF limits) :thumbsup:

joolsplus3
07-17-2007, 09:22 AM
I'm looking for the supposed studies from "Europe" which showed rear facing is unsafe past 25 lb. I found this instead:

Inertial Neck Injuries in Children Involved in Frontal Collisions (http://www.sae.org/technical/papers/2007-01-1170)

Can't find the full text elsewhere, and I'm not dishing out $14 to read it.

Hmmm...if you're looking to refute freakonimics, I posted the link from CHOP a few months ago (Tiffany? You have that still? I don't have time to look for it again).

Anyway, this study is saying to RF a long time? :whistle: That Australia and Canada's 'solution' of top tethering isn't as great as they think it is? I dunno, my brain's not up yet....

UlrikeDG
07-17-2007, 10:56 AM
They don't actually compare RF to FF, just FF to Booster. They found an increased risk with booster vs FF seat, even when the straps on the FF seat were looser than they should be (although looser straps did increase the risk as well).

Additionally, there was the possiblility for neck injury in frontal crashes even when CRS was the "safer" FF 5 point seat. It stops short of drawing conclusions about the relative safety of rear facing, as rear facing seats were not tested.

Now that I think about it, didn't The Freaks argue that boosters were stupid and didn't improve safety? If so, this study doesn't help. Late last night, I was thinking they had a slightly different take (i.e., that FF 5 points were the useless devices), which is why I thought this study was relevant to them specifically. It's still interesting, just not related to The Freaks. ;)

UlrikeDG
07-17-2007, 10:59 AM
Actually, the study only compares FF in a 5 point CRS vs Booster use. While it may be true that RF reduces the risk of neck injuries in 3 year olds, the only thing we can definitively say (based on this study) is that FF 5 point CRS do not provide 100% protection from neck injuries in severe frontal crashes, but they do provide more protection than a booster, even when the straps are too loose.

papooses
07-17-2007, 11:53 AM
Yeah, I see that now ... although I'm still drawing the same conclusion on my own that ERF is what it leads up to :p

joolsplus3
07-17-2007, 02:03 PM
Yeah, the Freaks only looked at FARS data and 'any' kind of restraint use for kids over 24 months old and said ANY kind of restraint use is pointless, from a death-rate perspective (they go on to say get the kid a DVD player... um... from an economics perspective, isn't a cheap cosco TONS cheaper than a DVD player and years and years of DVD purchases just to keep your kid sitting still in the back seat? Talk about bizarro logic on their part, huh?). They also ignored injury rates. Try googling 28 out of 100 and CHOP, because that's the kids that would have been saved/uninjured if sitting in a seat rather than seatbelt/unrestrained alone.

UlrikeDG
07-17-2007, 02:16 PM
Ah, then this study does refute them a bit, in that it shows that a 5 point harness helps reduce neck injuries. Doesn't go all the way, but still, it's something.

Jeanum
07-17-2007, 03:07 PM
Was this CHOP press release what you were looking for? http://www.prnewswire.com/cgi-bin/micro_stories.pl?ACCT=159681&TICK=CHOP&STORY=/www/story/06-05-2006/0004374684&EDATE=Jun+5,+2006 I think this was their study in response to Freakonomics.