McRae‐Clark 2015.

Methods	Randomised placebo‐controlled trial
Participants	Setting: outpatient (no further details on site, appears to be a single site). Scheduled duration 12 weeks Participants: 175 adults, current cannabis dependence by DSM‐IV Group sizes: group 1, 88; group 2, 87 Groups similar on demographics and clinical characteristics at baseline Mean age 24 years 77% male 64% Caucasian Exclusion criteria: current dependence on other substances except caffeine and nicotine, and significant psychiatric condition
Interventions	Group 1: buspirone, up to 60 mg/day Group 2: placebo Brief MET intervention and contingency management to encourage study retention as adjunct interventions
Outcomes	Participants with ≥ 1 negative urine test during treatment Point prevalence of abstinence by urine test at week 12 Number reporting adverse events
Notes	Funding: research grant (NIDA) 2 authors report previous pharmaceutical company funding
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method of sequence generation not described
Allocation concealment (selection bias)	Unclear risk	Method of allocation concealment not described
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "Buspirone and placebo tablets were packaged in identical opaque gelatin capsules with lactose." Comment: it was likely that participants and treating clinicians were blind to group allocation.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Double‐blind likely as indicated above, and only objective outcomes reported which are less likely to be affected by knowledge of group allocation.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Rates of attrition high, but similar in both groups. Missing data on cannabinoid urine tests counted as positive.
Selective reporting (reporting bias)	Low risk	None apparent, published outcomes accorded with prospectively registered outcomes.
Other bias	Low risk	None apparent