Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Withdrawal scores
[33] Systematic review	432 people 4 RCTs in this analysis	Mean peak withdrawal score with buprenorphine with methadone	SMD –0.45 95% CI –0.64 to –0.25 P <0.00001	Effect size not calculated	buprenorphine