Consumer Reports

Consumer Reports created a scoring system to judge headlights.

This system is intentionally subjective, and not scientific. They refer to metrics including distance, reach, intensity, smoothness, and glare. 

The test is performed in some part by setting up objects and seeing how well they are illuminated from a distance.

The lack of scientific basis for this testing has driven professional optical engineers crazy. It is difficult for them to understand why some headlights are rated "good" or "bad" by Consumer Reports.