Results of a Split Face Comparison conducted at the Department of Dermatology at Stanford University Medical Center (Volume 34 Issue 6, Pages 763 - 772, Published March 3, 2008) found that of nine participants who underwent three treatments each, using erbium resurfacing on one side of the face and intense pulsed light phototherapy on the other. They experienced no significant difference between the randomly assigned sides. The conclusion of this study was that patients preferred the light-based treatment because it resulted in less downtime.