The right used car for your child seat is going to be one with the easiest-to-reach anchors. That is just as important - if not more so - than airbags.

The Insurance Institute for Highway Safety has come out with a list of 2011 models that have easy to install children's seats in using the LATCH system, which stands for Lower Anchors and Tethers for Children. It also has the list of vehicles not meeting its guidelines.

Now, some may wonder why this list is important. After all, once a car seat is installed you can forget about it, right? Nope. You should test your car seats every time you fill up the gas tank. See if they are starting to wiggle. If they are, remove them and reinstall them so they are as tight as possible. A good car seat properly installed is not going to wiggle. Experts say the seat should not move more than an inch.

As a new car reviewer, I drove scores of cars, trucks, SUVs and crossovers when my daughters were young. Weekly I was swapping out car seats. I grew to detest some models because installing the latches to the anchors was almost impossible. On one car I actually had to cut the opening to get the anchors in. (Lets keep that last little nugget of info amongst ourselves.)

IIHS Researchers identified three factors associated with correct lower anchor use: depth, clearance and force.

1. Depth: Lower anchors should be located no more than 3/4 inch deep in the seat bight and should be easy to see.

1. Clearance: Nothing should obstruct access to the anchors. Safety belt buckles and other hardware plus the foam, cloth or leather material of the seats themselves shouldn't get in the way of attaching child seat connectors. There should be enough room around the anchors to approach them at an angle, as well as straight-on. This makes it easier to hook or snap on connectors and also tighten LATCH straps. In the study, a clearance angle of at least 54 degrees was associated with easier installation.
2. Force: Parents should be able to install child restraints using less than 40 pounds of force. Some systems require lots of effort to properly attach child seat hardware with lower anchors, in part because they are deep in the seat bight or surrounded by interfering parts of the vehicle seat.

(Not sure if you are properly installing car seats? Here is a baby seat installation video that should help you as well as a toddler seat installation video, too, from fellow experts here at About.com)

In order to be considered a recommended model, the LATCH system had to meet those three criteria. According to the IIHS, all three factors are related and are good predictors of how well people are able to correctly install child restraints. Vehicles meeting the criteria were 19 times as likely to have lower anchors used correctly by the volunteers compared with vehicles that don't meet any of the criteria.

2011 models that meet all 3 easy-installation criteria (Editor's note: the list is presented in alphabetical order as is the list following.)

• Audi A4 Quattro
• Cadillac Escalade
• Chevrolet Equinox LT
• Chevrolet Silverado 1500 crew cab
• Chevrolet Suburban LT
• Chevrolet Tahoe LS
• Chrysler Town & Country (2010)
• Dodge Caliber Mainstreet
• Dodge Grand Caravan Crew
• Dodge Ram 1500 crew cab
• Ford Escape XLT
• Ford F-150 SuperCrew Cab
• GMC Sierra 1500 crew cab SLE
• Honda Pilot EX-L
• Kia Sedona LX
• Land Rover Range Rover Sport
• Mercedes-Benz C300
• Mercedes-Benz E350
• Mitsubishi Eclipse coupe GS
• Mitsubishi Lancer ES
• Toyota Tacoma extended cab

The following models failed to meet any of the three criteria for child seat use. You are going to have to strongly take that into consideration before buying any of these models. But, and there is always a but, you should take the child seat you plan to use and test it in the used car you plan to purchase. You might find you can overcome the problems.

Also, note the trim level on the list below. A lot of the models mentioned have leather seats, which can be a huge factor in degree of difficulty. Models with cloth seats may not give you the same problems.

2011 models that don't meet any easy-installation criteria

• Buick Enclave CX
• Chevrolet Impala LT
• Dodge Avenger Express
• Ford Flex SEL
• Ford Taurus Limited
• Hyundai Sonata Limited
• Toyota Sienna XLE

Kind of interesting to see the ultimate family vehicle - the Toyota Sienna XLE minivan - on the list of used cars with a bad child safety seat rating. That just demonstrates how thorough you have to be when used car shopping.

So, after reading all of this info on car seats, keep one important piece of advice in mind. When used car shopping, always leave the kids at home. It's going to make testing the car seats a lot easier.