The SUMMIT trial: a field comparison of buprenorphine versus methadone maintenance treatment. 
This prospective patient-preference study examined the effectiveness in practice of methadone versus buprenorphine maintenance treatment and the beliefs of subjects regarding these drugs.  A total of 361 opiate-dependent individuals (89% of those eligible, presenting for treatment over 2 years at a drug service in England) received rapid titration then flexible dosing with methadone or buprenorphine; 227 patients chose methadone (63%) and 134 buprenorphine (37%).  Participants choosing methadone had more severe substance abuse and psychiatric and physical problems but were more likely to remain in treatment.  Survival analysis indicated those prescribed methadone were over twice as likely to be retained (hazard ratio for retention was 2.08 and 95% confidence interval [CI] = 1.49-2.94 for methadone vs. buprenorphine), However, those retained on buprenorphine were more likely to suppress illicit opiate use (odds ratio = 2.136, 95% CI = 1.509-3.027, p < .001) and achieve detoxification.  Buprenorphine may also recruit more individuals to treatment because 28% of those choosing buprenorphine (10% of the total sample) stated they would not have accessed treatment with methadone.