Group treatment for substance use in adults

A systematic review with meta-analysis (Lo Coco et al 2019, 33 RCTs, n= 3951) of substance use treatment interventions in group settings found:

• significant small effects on abstinence when compared to no treatment (SMD 0.28, 95% CI 0.04 to 0.52), individual therapy (SMD 0.34, 95% CI 0.06 to 0.62), and other treatments (SMD 0.29, 95% CI 0.07 to 0.50).
• no significant effects on substance use frequency when compared to individual therapy (SMD 0.52, 95% CI -0.25 to 1.28), and other treatments (SMD 0.01, 95% CI -0.14 to 0.16).
• significant moderately sized effects for mental state when compared to no treatment (SMD 0.64, 95% CI 0.38 to 0.90).
• no difference in abstinence rates when compared to control groups.

Interventions addressed the use of alcohol, cocaine, heroin or opioids, and cannabis.