Table 2. Median retention rates across included studies.
| Retention 6 months % (range) | Retention 12 months % (range) | Retention 2 years % (range) | Retention 3 years % (range) | |
|---|---|---|---|---|
| MMT | 67.0% (46.8%–86.0%) | 60.7% (20.3%–94.0%) | 49.8% (29.5%–76.0%) | 54.0% (20.0%–82.0%) |
| [n = 9] (63, 65, 66, 74, 75, 78, 79, 81, 83) | [n = 24] (35–37, 46, 48, 54, 55, 59–63, 65, 66, 73–75, 77, 79, 81, 85, 91, 92, 94) | [n = 7] (42, 48, 63, 74, 89, 92, 94) | [n = 6] (37, 46, 59, 91, 92, 94) | |
| BUP | 56.8% (19.1%–64.0%) | 45.4% (11.7%–61.6%) | - | - |
| [n = 5] (49, 58, 70, 82, 88) | [n = 6] (49, 68, 69, 72, 84, 93) | |||
| Mixed OST | 54.0% (52.6%–75.8%) | 40.4% (33.0%–65.8%) | - | - |
| [n = 5] (44, 47, 51, 86, 87) | [n = 7] (41, 44, 51–53, 86, 87) | |||
| Overall | 58.0% (19.1%–86.0%) | 57.0% (11.7%–94.0%) | 49.8% (29.5%–76.0%) | 38.4% (13.7%–82.0%) |
| [N = 19] (44, 47, 49, 51, 58, 63, 65, 66, 70, 74, 75, 78, 79, 81–83, 86–88) | [N = 37] (35–37, 41, 44, 46, 48, 49, 51–55, 59–63, 65, 66, 68, 69, 72–75, 77, 79, 81, 84–87, 91–94) | [N = 9] (42, 48, 51, 63, 72, 74, 89, 92, 94) | [N = 8] (37, 46, 59, 68, 69, 91, 92, 94) |
Median retention rates for buprenorphine and mixed OST are not reported at 2 and 3 years follow-up due to small study numbers (buprenorphine at 2-years (n = 1); buprenorphine at 3 years (n = 2); mixed OST at 2 years (n = 1); mixed OST at 3 years (n = 0)