Barnett 2007.

Methods	RCT.
Participants	225 US college students referred to attend alcohol education following an alcohol‐related incident.
Interventions	Brief MI (n= 112) vs. computer‐delivered education (Alcohol 101 CD ROM, [n=113]).
Outcomes	Physiological primary: None. Non‐physiological primary: Number of drinking days, number of heavy drinking days, average number of drinks per drinking day, average estimated BAC, alcohol problems. Secondary: Motivation to change alcohol use (Contemplation Ladder).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random numbers table.
Allocation concealment (selection bias)	Unclear risk	"The counsellor opened an envelope containing the baseline condition assignment, prepared by the project coordinator". It remains unclear whether envelopes were sequentially numbered, opaque and sealed.
Blinding (performance bias and detection bias) Patients and providers	High risk	No blinding.
Blinding (performance bias and detection bias) Assessors	Low risk	"A research assistant who was blind to intervention condition conducted the 3‐ and12‐month follow‐up assessments in person, or by phone and mail..."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	5% attrition at 3 months follow‐up and 6% attrition at 12 months follow‐up with no differences between conditions. Reasons for missing data not stated. ITT not performed.
Selective reporting (reporting bias)	Low risk	The published report included all expected outcomes based on the stated hypotheses.
Other bias	Unclear risk	Only self‐reported outcomes. There were no differences between groups at baseline.