Therapeutic Workplace Maintenance Study

STUDY PARTICIPANTS This study was approved by the Western Institutional Review Board. Participants were recruited in methadone clinics throughout Baltimore. Recruitment began in October 2003, and the study was completed in August 2007. Of the 251 individuals assessed for eligibility, 128 met these criteria and were invited to participate in the study.

SETTING The study was conducted at the Center for Learning and Health, Johns Hopkins School of Medicine, Baltimore, MD. The workplace included a sign-in station, a urinalysis laboratory, and three workrooms. The workrooms contained 47 computer workstations.

PRE-RANDOMIZATION PROCEDURES Intake Assessment At intake, participants signed informed consent and completed an interview. Urine samples were collected and tested for cocaine, opiates, benzodiazepines, methadone, and amphetamines. A questionnaire was administered to assess participants' capacity to operate a keyboard. The Composite International Diagnostic Interview (CIDI), 2nd ed. was administered to assess drug dependence. Other assessment tools included the Addiction Severity Index - Lite (ASI-Lite), the Risk Assessment Battery (RAB), the Wide Range Achievement Test (WRAT-3), and a reading assessment. Participants were paid $30 in vouchers for completing the interview.

Workroom and Urinalysis Procedures Eligible participants were enrolled in phase 1 and could work in the workplace from 10 AM-12 PM and 1 PM-3 PM every weekday for 6 months. During this phase, participants worked on computerized training programs designed to teach them to become data entry operators. On Monday, Wednesday and Friday, participants provided a urine sample under observation. Breath samples were tested for alcohol. Urine samples were tested for opiates and cocaine and participants received graphs showing current and prior drug test results. Participants earned a base pay of $8.00 per hour in vouchers. Additionally, participants could earn approximately $2.00 per hour in vouchers in productivity pay for working on training programs. Earnings accumulated in the participant's account until exchanged for a gift card or other approved goods and services.

Initially, participants could attend the workplace independent of their urinalysis results. This "workplace induction" continued for at least 4 weeks and until the participant worked for at least 5 min on 15 workdays. After workplace induction, participants were required to provide evidence of cocaine abstinence to work and to maintain maximum pay. Specifically, participants gained access to their workrooms if urinary benzoylecgonine concentration was <300 ng/mL or at least 20% lower per day since the last sample submitted. Participants who provided a cocaine-positive urine sample could not work until they provided a new sample that met the criteria. Upon return to work, the rate of base pay was reduced to $1.00 per hour. Base pay was then increased by $1.00 per hour every day that a participant provided a sample that met the criteria and worked at least 5 minutes until reaching $8.00 per hour. Missing samples were treated as positive. After a participant provided cocaine-negative samples for three consecutive weeks, the abstinence contingency was extended to opiates (ie, urinary benzoylecgonine and morphine concentrations of <300 ng/mL, or decreases in benzoylecgonine and morphine concentrations by at least 20% per day since the last sample submitted). After providing cocaine- and opiate-negative samples for three consecutive weeks the contingency was expanded to include alcohol if the participant had provided alcohol positive (≥0.003 ng/L) samples during the opiate and cocaine contingency period. This stepped contingency program is described in detail elsewhere.