The U.S. Department of Energy's CALiPER program has released Report 20.3, which is part of a series of investigations on LED PAR38 lamps. Report 20.3 focuses on an evaluation of robustness. Three samples each of 40 of the Series 20 PAR38 lamps (including LED and benchmark conventional lamps) underwent multi-stress testing, whereby samples were subjected to increasing levels of simultaneous thermal, humidity, electrical, and vibrational stress. The results don't explicitly predict expected lifetime or reliability, but they can be compared with one another, as well as with benchmark conventional products, to assess the relative robustness of the product designs.