After many vehicles posted consisted four- or five-star ratings under safety tests issued by the National Highway Traffic Safety Administration (NHTSA), the agency revised its tests to become much more stringent, resulting in a drop-off for a number of popular vehicles.

The group is slowly making their way through batches of vehicles, and the latest tests exposed the safety flaws in one top-selling model: the Honda Civic. The Civic scored a two out of five in the side crash test and went home with an overall score of 3, a significant difference from the car's once 5-star reputation.

Honda is no slouch when it comes to safety, as the company's Accord has been the only model thus far to crack the new tests, earning a five in the rollover, side crash and frontal crash tests for a perfect score. Most cars receive a three- or four-star overall rating.

The other cars tested were the Nissan Sentra, Chevy Equinox and GMC Terrain. The Terrain and Equinox received five stars in side crashes and fours in the other two categories. The Sentra got a four in the rollover, but could only manage threes in the front and side crash tests.

Drivers should consider safety ratings when shopping for new or used vehicles.