Efficacy of urine monitoring in methadone maintenance.

To test the efficacy of screening urine specimens of methadone maintenance clients as a deterrent to illicit drug use, the authors randomly assigned 431 subjects to a monitored or an unmonitored group for 1 year. Monitored subjects continued to provide urine specimens once a week; unmonitored subjects did not. All other aspects of treatment remained the same. At 4 and 8 months after the study began, surprise urine collections were conducted. There was no difference between the groups in the proportion of drug-free specimens at either time.