Urine testing in methadone maintenance treatment: applications and limitations.

We consider here the applications and limitations of urine testing schedules used in methadone maintenance treatment programs. We show that for patients attending clinic daily, any practical testing schedule will only reliably detect those who are using heroin or other illicit drugs very frequently (e.g., daily). For patients with take-home privileges no testing schedule can effectively detect either skipped doses or use of illicit drugs. Consequently, whether for patients attending clinic daily or for patients with take-home privileges, some programs, as measured by urine test results, may actually be less successful than they appear to be.