After a half-century of trying everything from Accutane to zinc, dermatologists still don't know which acne treatments work best. The problem lies with the dearth of studies directly comparing treatments, said Harold P. Lehmann, MD, PhD, a Johns Hopkins pediatrician and an author of Management of Acne, a thorough review (available at http://www.ahrq.gov/clinic/acnesum.htm) of the literature funded by the Agency for Healthcare Research and Quality.
Vastag B. Best Acne Treatment Elusive. JAMA. 2001;285(19):2439. doi:10.1001/jama.285.19.2439-JHA10004-4-1