The Insurance Institute for Highway Safety, a non-profit group funded by the insurance industry, rated 2013-2014 vehicles on how well their advanced-technology features help drivers avoid collisions.
IIHS focused on two systems, front collision warning and automatic brakes, which are typically offered as extra-cost options on an increasing number of new cars.
The group tested 74 "moderately priced" and luxury midsize cars and crossovers. IIHS awarded a "superior" rating to seven: General Motors Co's Cadillac ATS sedan and Cadillac SRX crossover; Geely Holding Group Co's Volvo S60 sedan and Volvo XC60 crossover; Fuji Heavy Industries Ltd's Subaru Legacy sedan and Subaru Outback wagon, and Daimler AG's Mercedes-Benz C-Class sedan.
The top rating is given to vehicles equipped with automatic brakes that can substantially slow down a vehicle or help it avoid a crash in tests at 12 and 25 miles per hour, IIHS said.
Automatic brakes can reduce vehicle speed or, in some cases, completely stop a car without driver intervention. They are marketed under a variety of names by different manufacturers.
Volvo's automatic braking system, called City Safety, is the only such system offered as standard on the vehicles tested by IIHS. The S60 and XC60 also can be ordered with an optional safety system called Collision Warning with Full Auto Brake and Pedestrian Detection.
Subaru's automatic brake system, which includes a pair of small cameras to monitor traffic, is called EyeSight and is an option on the Legacy and Outback. Cadillac's Automatic Collision Preparation, another auto-brake system, is an option on the ATS and SRX.
IIHS also tests and rates new vehicles in side, rear, rollover and front-end crashes.