Pengpid 2013a.

Study characteristics
Methods	Study design: randomized controlled trial Country: South Africa Setting: university Eligibility criteria: included were university studies 18 years of age and older who visited public recruitment venues at the university campus and who were risky drinkers (AUDIT>=8). Excluded were students who were pregnant or already in alcohol treatment. Duration of follow‐up: 12‐months Informed consent: all participants provided informed consent Ethical approvals: Medunsa Research and Ethics Committee
Participants	Sample size: 152 (81 intervention 71 control) Description of the target population: university students with risky drinking Age: 21.9 years (SD = 3.5) Sex: 12.7% female Race/Ethnicity: not reported Marital status: not reported Harmful alcohol use (baseline): AUDIT=16.2 (SD=7.1) Co‐occurring disorders: 23.8% PTSD, 12.6% Depression
Interventions	Type: non‐pharmacologic Description: Brief intervention including personalized feedback, health education, simple advice, brief counseling about reducing excessive drinking informed by the Information‐Motivation‐Behavioral Skills Model Duration and frequency: one 20‐minute session Delivery and provider: Nurse counselor Comparison group: one health education session focused on responsible drinking and feedback on alcohol screening delivered by a nurse counselor
Outcomes	Primary outcome(s): hazardous alcohol use Primary outcome measurement tool(s): AUDIT Secondary outcome(s): heavy episodic drinking, PTSD symptoms, Depressive symptoms, High risk alcohol use, Alcohol dependence, Secondary outcome measurement tool(s): AUDIT, 7‐item PTSD screener, CES‐D Time points: 0, 6, 12‐months
Notes	Study funding and conflicts of interest: Directorate General for Development Corporation (DGDC) through the Flemish Interuniversity Council (VLIR‐UOS) Linked study records: None
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "After baseline assessment, each student was randomized to either a control or a brief intervention group. Students were randomized using sequentially numbered opaque sealed envelopes prepared according to a computer‐generated (prepared using Stata version 10) randomization allocation sequence. This was carried out separately by an off‐side data management group. After randomization interventionists were instructed to implement the brief intervention." Pg. 2045
Allocation concealment (selection bias)	Low risk	Quote: "Students were randomized using sequentially numbered opaque sealed envelopes prepared according to a computer‐generated (prepared using Stata version 10) randomization allocation sequence." Pg. 2045
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "Research assistant nurses and university students were not blind to their intervention." Pg. 2046
Blinding of outcome assessment (detection bias) All outcomes	High risk	Outcomes reported by participant not blind to intervention Quote: "However, to protect against information biases in the reporting of alcohol use behaviour, the data collection team who assessed the outcomes were blind to the client’s status as intervention arm." Pg. 2046
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Quote: "The extent of the missing component was 3.3% at 12 months. The single follow‐up measurement and the extent of the expected dropout was considered for the statistical method that was used to provide an unbiased estimate of the intervention effect under the principle of intention to treat." Pg. 2049
Selective reporting (reporting bias)	Unclear risk	Protocol not available