When the Insurance Institute for Highway Safety crashed a 2012 Fiat 500, the little car got the best scores in all categories. It’s a safe car, then, right?

“If safety is a priority, you should avoid the smallest cars,” advises Russ Rader, spokesperson for IIHS. “Weight counts. Smaller, lighter cars are safer than they used to be, but all things being equal, people riding in bigger, heavier vehicles get more protection in crashes.”

That’s why, despite its near-perfect crash-test score, the Fiat 500 is No. 1 on Insure.com’s list of worst vehicles for protecting passengers from injuries. In an accident with a larger object, the Fiat’s safety cage and array of air bags do what they can to protect passenges, but like eggs in a coffee can, the passengers get thrown about and smashed up.

If the Fiat 500 is like a coffee can, then a fullsize GMC pickup (which tops the website’s list of vehicles best at protecting passengers) would be a 50-gallon barrel. In a collision between the two, the barrel of eggs will win every time. The GMC Sierra 1500 is rated best at protecting passengers by Insure.com, but IIHS rated it just average in the side impact test and marginal in the roof strength test. Second place on Insure.com’s best list is the Porsche Cayenne, which has not been tested by IIHS. The third through fifth place spots go to the GMC Yukon, Sierra 2500 and Terrain.

The listings are the result of Insure.com’s analysis of personal injury protection and medical payment claims which affect what car owners are charged for insurance.