Carey 2006.

Methods	RCT.
Participants	509 US heavy drinking students.
Interventions	1. Timeline Follow‐Back control (n= 89) 2. TLFB basic MI (n= 87) 3. TLFB enhanced MI (n= 86) 4. control (n= 81) 5. basic BMI (n= 85) 6. enhanced BMI (n= 81).
Outcomes	Physiological primary: None. Non‐physiological primary: Drinks per week, drinking per drinking day, heavy drinking frequency, peak BAC, RAPI score. Secondary: None.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Assigned randomly".
Allocation concealment (selection bias)	Unclear risk	Insufficient information to permit judgment.
Blinding (performance bias and detection bias) Patients and providers	High risk	No blinding.
Blinding (performance bias and detection bias) Assessors	High risk	Assessors "were not blind to condition."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	3% lost to follow‐up at one month, 23% at 6 months and 22% at 12 months. Balanced across conditions. Reasons for missing data addressed but not detailed. Unclear whether ITT was used.
Selective reporting (reporting bias)	Low risk	The published report included all expected outcomes based on the stated hypotheses.
Other bias	Low risk	Collateral report as check of self‐report. There were no differences between groups at baseline. No additional sources of bias appear to be present.