Eisen 2012.

Methods	Allocation: randomised Blindness: not stated Study duration: 3 months Location: multicentre Design: parallel Setting: inpatients Country: USA Consent: written
Participants	Diagnosis: psychotic disorders, depressive disorder, alcohol‐use disorder or substance‐use disorder N = 298 History: not stated Sex: men 220, women 78 Age: range 30–60 years Exclusion criteria: not stated
Interventions	Group 1: peer‐support + standard care (n = 74). Content: peer facilitators used written recovery material such as the Spanior Recovery Workbook available from the Boston University. Peer leaders also shared their personal experiences as veterans with mental illness. Delivered by: 2 peer facilitators. Frequency: group met for 45 minutes weekly. Treatment duration: 12 weeks. Group 2: clinician‐led recovery + standard care group (n = 82). Content: clinician‐led recovery group. Delivered by: 1 Master's‐level clinician. Treatment duration: 45 minutes weekly. Group 3: standard care (n = 84). Content: treatment as usual group. Details not reported.
Outcomes	Global state: general health (VR‐12) Mental state: empowerment, hope, mental health Behaviour: recovery, activation Peer outcomes: social support Unable to use Global state: leaving the study early (data were not reported by each group). Mental state: depression, self‐harm, emotional liability, interpersonal relationship, psychotic symptom (skewed data) Behaviour: alcohol use (skewed data)
Notes	Funding source: study was supported by the VA Rehabilitation Research and Development Service grant D4464R. We contacted author to clarify the proportion of schizophrenia but received no reply.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Veterans were randomly assigned to...", "the random assignment was in an envelope." Comment: trials were randomised with allocation concealment. Under this condition, we assumed the author did the random sequence generation adequately.
Allocation concealment (selection bias)	Low risk	Quote: "the random assignment was in an envelope." Comment: allocation concealment ensured.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: the author did not describe the blinding of participants and personnel. Insufficient information to make judgement.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: the author did not describe the blinding of outcome assessment. Insufficient information to make judgement.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "Of these (298 veterans), 240 (81%) completed the three‐month follow‐up and were included in the analyses." Comment: low attrition rate and participants leaving early were balanced in groups. Analysis of attrition was included in the study.
Selective reporting (reporting bias)	Unclear risk	Comment: protocol not available. Insufficient information to make judgement.
Other bias	Low risk	None noted.