Martino 2006.

Methods	Pilot RCT.
Participants	44 dually diagnosed psychotic and drug‐related disordered patients. USA.
Interventions	Two sessions of MI (n=24) vs a two‐session standard psychiatric interview (n=20).
Outcomes	Physiological primary: None. Non‐physiological primary: Days of primary drug use, secondary drug use, alcohol use. Secondary: Retention in treatment. Readiness to change (URICA). Data not reported. Follow‐ups were at posttreatment, 1, 2, and 3 months.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Urn randomisation.
Allocation concealment (selection bias)	Unclear risk	Insufficient information to permit judgement.
Blinding (performance bias and detection bias) Patients and providers	Low risk	Blinding of providers was not possible, but participants could have been blinded.
Blinding (performance bias and detection bias) Assessors	Low risk	"...two research staff members administered the assessments in a non‐blinded fashion."
Incomplete outcome data (attrition bias) All outcomes	Low risk	14% were lost to at least one follow up, balanced across groups. Reasons for loss not stated. ITT performed.
Selective reporting (reporting bias)	Low risk	The published report included all expected outcomes based on the study purposes.
Other bias	High risk	Only self‐reported outcomes. There were differences at baseline in alcohol composite score and legal involvement.