Dobson 1995.

Methods	Allocation: randomised. Blinding: no (raters blinded). Duration: 11 weeks (3 months follow‐up).* Setting: inpatients. Design: parallel. Country: Canada.
Participants	Diagnosis: schizophrenia (structured clinical interview for DSM‐III‐R). N = 33. Sex: M 21, F 12. Age: 18‐ 55 years. History: schizophrenic, 18 to 55 years, low‐average intelligence or higher.
Interventions	1. Social skills training: first three weeks ‐ basic communication skills; second three weeks ‐ assertiveness training; third three weeks ‐ individual communication and assertive goal setting. Four one‐hour sessions per week over nine week period (N = 18). 2. Social milieu: structured activities including supportive discussion groups, exercise groups and activity groups. Occurred at same time of day and same length of time as social skills training group (N = 15). Neuroleptic medication for all patients.
Outcomes	Leaving the study early. Unable to use ‐ Mental state: PANSS (no SDs). Relapse and re‐hospitalisation (confounding effect of social milieu participants beginning social skills training*)
Notes	* One week of assessments before the treatment, nine weeks of treatment, and one week of assessments after the treatment. Three month follow‐ups were completed for all patients, at that point social milieu participants were able to participate in social skills training. The social skills group received additional assessment at 6 months follow‐up. Rehospitalisation data and relapse data were collected on all patients at 6 months and 1 years after treatment.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly assigned" no further information given.
Allocation concealment (selection bias)	Unclear risk	No information provided.
Blinding (performance bias and detection bias) All outcomes	High risk	Single blind: "None of the assessments were completed by the group therapists for subjects in the study, and none of the treatment groups were led by the investigators".
Incomplete outcome data (attrition bias) All outcomes	High risk	There were 5 dropouts: 2 from the social milieu group and 3 from the social skills group. "The reasons they gave for dropping out were unrelated to the treatment".
Selective reporting (reporting bias)	High risk	Not all expected outcomes reported.
Other bias	High risk	Protocol not available. The follow‐up period for social milieu group was limited mid‐study so they could also receive social skills training, which they had expressed interest in to the investigators.