Stein 2006.

Methods	Design: RCT Follow‐up: 3 months Attrition: 17%
Participants	Mean age (years): 17.06 Sex: 89.5% male N participants: 105 Allocation: n = 59 intervention; n = 46 control Setting: state juvenile correctional facility; higher risk substance using youth Country: USA
Interventions	Programme type: motivational interviewing Set‐up: individual single session Key components: developing rapport, exploration of motivation (pros and cons), personalised assessment feedback, imagining the future with and without change, and establishing goals Duration:  90 min with 60 min booster session Control: alternative intervention
Outcomes	Outcomes: risky behaviours including driving under the influence of alcohol Measures: adaptation of Young Adult Drinking and Driving Questionnaire
Funding and Declared Conflicts of Interest	Funded by NIDA. No information or declarations about potential conflicts of interest.
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information to permit judgement
Allocation concealment (selection bias)	Unclear risk	Insufficient information to permit judgement
Incomplete outcome data (attrition bias) All outcomes	Low risk	Low attrition (17%)
Selective reporting (reporting bias)	Low risk	All outcomes reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible to blind participants to intervention. Insufficient information to make a judgement about blinding of therapists
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information to permit judgement
Unit of Analysis issues	Low risk	Not applicable