Tesla EV Rated Safest Among 130 Cars Tested by NHTSA

Tesla Motors Inc.'s Model S electric sedan has earned the best overall vehicle safety score among all current model year cars tested by the National Highway Traffic Safety Administration.

Tesla trumpeted the results earlier this week by creating its own six-star safety rating system and giving itself 5.4 stars. NHTSA's rating system ranges between one and five stars.

The agency says that in the current batch of 2013 models it has crash tested, 75 of 130 vehicles earned its top five-star combined score. The agency adds that it does not rank vehicles within those five categories.

But NHTSA also calculates a separate "combined vehicle-safety score" for manufacturers that does reveal model-to-model differences. Here is where the Model S outperformed all other vehicles on the agency's list.

The combined vehicle-safety index shows the probability of being injured in a vehicle that crashes. In this case, a lower number is better.

Among this year's five-star-rated vehicles, the vehicle-safety index ranges from 0.42 for the Model S to 0.66 for the Lincoln MKZ large sedan. The worst of the vehicle-safety scores 1.67 is shared by the Chevrolet Silverado and GMC Sierra large pickup trucks.