Woods 2012a.

Methods	Multicentre RCT.
Participants	488 participants living in the community meeting DSM‐IV criteria for dementia. Participants participated in dyads with informal carers, most of whom were spouses. Mean age: 77.5 years.
Interventions	Intervention: joint reminiscence groups for the person with dementia and their carer. Control: treatment as usual.
Outcomes	Quality of life: QoL‐AD, QCPR, EQ‐5D. Cognitive: AMI‐E. Behavioural: BADLS. Mood‐related outcomes: CSDD, RAID. Carer: GHQ‐28, HADS, RSS, QCPR, EQ‐5D.
Length and frequency of intervention	1 × 2‐hour session per week for 12 weeks followed by 1 maintenance session per month for 7 months.
Time points measured	Baseline before randomisation, 3 months postbaseline (following completion of the weekly reminiscence sessions) and 10 months postbaseline (following completion of the monthly maintenance reminiscence sessions).
Number of participants who did not complete study	138/488 dyads (28.28%).
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was completed using a dynamic allocation method stratifying for spousal or non‐spousal relationship of the dyad. Complete list randomisation for each wave of recruitment within each centre was completed by an accredited trials unit.
Allocation concealment (selection bias)	Low risk	By undertaking a complete list randomisation for each wave at each centre, allocation knowledge of the next assignment would be irrelevant as all participants for a centre would be randomised together.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Unblinded researchers (responsible for allocation and running sessions) were the only staff informed at each of the centres of the participant's allocation. Researchers blinded to group allocation carried out all follow‐up assessments.
Incomplete outcome data (attrition bias) All outcomes	Low risk	137 total withdrawals from trial including 29 deaths. Reasons included death, ill health, no wish to continue, family circumstances, no time and no reason given. 1 dyad was excluded due to re‐recruitment. A linear regression model was applied to take missing data into account.
Selective reporting (reporting bias)	Low risk	All outcomes listed in the methods section and study protocol were reported. There was no evidence of selective outcome reporting.
Other bias	Low risk	n/a.
Availability of training and supervision Objective outcome measures	Low risk	2 × half day training sessions for volunteers and facilitators took place before each group commenced.
Availability of manual or protocol for intervention All outcomes	Low risk	Intervention followed the RYCT manual.