The New England Journal of Medicine published a study comparing methadone with LAAM and buprenorphine. The authors concluded that "Levomethadyl acetate, buprenorphine, and high-dose methadone were all effective in treating opioid dependence and were were superior on multiple measures to low-dose methadone. The percentage of patients retained at 17 weeks compared favorably with rates reported elsewhere for these medications."

Source

Johnson, Rolley E., Pharm. D., Mary Ann Chutuape, PhD, Eric C. Strain, MD, Sharon L. Walsh, PhD, Maxine L. Stitzer, PhD, and George E. Bigelow, PhD, "A Comparison of Levomethadyl Acetate, Buprenorphine, and Methadone for Opioid Dependence," New England Journal of Medicine (Boston, MA: Massachusetts Medical Society, Nov. 2, 2000), Vol. 343, No. 18, p. 1295.
http://content.nejm.org/cgi/r…