First author and year, country (city) | Design | Sample description and N | Outcomes | Results |
---|---|---|---|---|
Havens 2009, USA, (Baltimore) [74] | Same RCT as Strathdee 2006 Intervention arm: Strength based case management (SBCM) Comparison arm: passive referral | RCT participants who successfully entered treatment (N = 127) | Predictors of retention in methadone treatment | Median duration in treatment was 7.9 months (IQR = 6–12.2 months) Adjusted HR for days retained in methadone: Treatment site ≥ 4.5 miles from home 2.15 (1.31–3.51); Lived in more than one place in last year 1.79 (1.10–2.92); Unemployed 0.37 (0.21–0.63); Previously enrolled in outpatient drug-free treatment 0.3 (0.13–0.71); Asked SSP twice or more for treatment slot 0.60 (0.36–0.97); Baseline ASI psychiatric score ≥ median score 2.22 (1.33–3.73) |
Bråbäck 2017, Sweden (Malmo)[43] | Same RCT as Bråbäck 2016 Intervention arm: CASE management plus referral Comparison arm: Referral alone | RCT participants who successfully enrolled in buprenorphine or methadone treatment (N = 71) | Treatment retention | 3, 6 and 12 month retention: 94%, 89%, 82% |
Kidorf 2018, USA (Baltimore) [42] | Intervention arms: 1) Low Threshold methadone Initiation (LTI) 2) Voucher Reinforcement Initiation (VRI) Comparison arm: Standard Care Initiation (SCI) | SSP participants newly initiating methadone treatment (N = 212) | Treatment retention | 3 month retention: (SCI: 31%; VRI: 34%; LTI: 35%, NS) 6 month retention: (SCI: 29%; VRI: 34%; LTI: 37%, NS) |
Kidorf 2021, United States (Baltimore) [46] | Same RCT as Kidorf 2018 Intervention arms: 1) Low Threshold methadone Initiation (LTI) 2) Voucher Reinforcement Initiation (VRI) Comparison arm: Standard Care Initiation (SCI) | RCT participants (N = 210) | Sexual risk behaviors over 6 months after starting methadone treatment | Sexual risk scores (range 0–18) decreased by 0.354 one month after enrollment (p < 0.01), but not significantly thereafter (p = 0.321) |
Kidorf 2021, United States (Baltimore) [45] | Same RCT as Kidorf 2018 Intervention arms: 1) Low Threshold methadone Initiation (LTI) 2) Voucher Reinforcement Initiation (VRI) Comparison arm: Standard Care Initiation (SCI) | RCT participants (N = 210) | Substance use risk behaviors over 6 months after starting methadone treatment | Drug risk scores (range: 0–22) decreased by 1.573 one month after enrollment (p < 0.01), with reductions of 0.129 per month thereafter (p < 0.01) |
Kidorf 2011, United States (Baltimore) [75] | Same RCT as Kidorf 2009 Intervention arms: 1) Motivational referral condition (MRC) 2) MRC + financial incentives (MRC + I) Comparison arm: Standard referral condition (SRC) | RCT participants who enrolled in methadone treatment vs. did not enroll (N = 240) | Risk behaviors over 4 months | Participants who enrolled in treatment reported less days of opioid (p < 0.01) and cocaine (p < 0.01) use, IVDU (p < 0.01), illegal activities (p < 0.01) and incarceration (p < 0.05) after 4 months |
Kuo 2003, United States (Baltimore) [76] | Cohort study | People with OUD enrolled in a single SSP for > 1 month who expressed interest in SUD treatment (N = 163) | (a) % enrolling in treatment (levomethadyl acetate hydrochloride (LAAM)), (b) treatment retention, and (c) early treatment response (UDT) and addiction severity index (ASI) scores | (a) 70% enrolled in LAAM (b) 84% actively enrolled after 90 days, mean duration treatment 8.1 months (c) 31.2% decrease in heroin positive (p < 0.01) and 22.5% decrease in cocaine positive (p = 0.01) UDT from month 1 to 3. ASI scores lower in drug (p < 0.01), alcohol (p < 0.01) and legal (p < 0.01) domain at 1 month |
Brooner 1998, United States (Baltimore) [12] | Cohort study | Patients admitted to methadone treatment referred from SSP vs. standard referral sources (N = 325) | (a) Treatment retention & (b) substance use | (a) 76% of SSP referred vs. 88% of other completed 13 weeks of treatment (p > 0.01); (b) SSP referred had more opioid positive (49% vs. 29% p < 0.01) and cocaine positive (54% vs. 32% p < 0.01) than standard referral sources during first 3 months of treatment |
Neufeld 2008, United States (Baltimore) [47] | Same study as Brooner 1998 Cohort study, outcomes extended to 12 months | Patients admitted to methadone treatment referred from SSP vs. other referral sources (N = 324) | (a) Treatment retention at 12 months and (b) substance use (UDT) | (a) 35% SSP referrals vs. 56% other referral source completed 365 days of treatment (p < 0.05); (b) SSP referred had negative UDTs for opioids (63% vs. 78%, p < 0.05), cocaine (57% vs. 75%, p < 0.05) and any drugs (45% vs. 62%, p < 0.05) |