Charlesworth 2016.

Methods	Factorial pragmatic RCT.
Participants	291 community‐dwelling people in the UK, with a diagnosis of dementia according to DSM‐IV and their family carers. 144 participants were in groups relevant to the current review. Mean age: 74.21 years.
Interventions	Intervention 1: group reminiscence (RYCT) for people with dementia and their carers (RYCT program) Control: treatment as usual Intervention 2: carer support programme. Intervention 3: both intervention 1 and intervention 2 The current review used data from participants in the RYCT (only) and treatment as usual (only) groups.
Outcomes	Quality of life: QoL‐AD, EQ‐5D, DEMQOL. Behavioural: ADCS‐ADL. Mood‐related outcomes: HADS, NPI, QCPR. Carer: mental component score of the UK Short Form‐12 Health Survey (UK SF‐12), EQ‐5D, HADS, Emotional Loneliness Scale, NPI‐D, PANAS, COPE‐PAC, PGI, QCPR.
Length and frequency of intervention	1 session, 2 hours per week, for 12 weeks. After the weekly sessions, monthly sessions continued for 7 months, giving a possible 19 sessions over 10 months.
Time points measured	Baseline, 5 months' postrandomisation and 12 months postrandomisation.
Number of participants who did not complete study	50/291 (17%); across all groups, including those not relevant to the current review. Specific attrition for each group not reported.
Notes	In group reminiscence sessions, family carers met separately from the main group for 45 minutes during 4 sessions, with the aim of developing listening and communication skills, and considering how the activities and strategies in the sessions could continue at home.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	A 2‐stage sequential dynamic algorithm was used to randomise participants. Randomisation was web based and was developed in collaboration with an accredited trials unit.
Allocation concealment (selection bias)	Low risk	The combination of the 2 randomisation stages resulted in participant allocation. An (unblinded) administrator then informed carers of their allocation by letter.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	All research interviewers who assessed outcomes were blinded. After interview, researchers recorded their perceptions of participants' allocation. This showed no evidence of bias due to non‐blinded researchers.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The authors reported "missing scores were imputed, with multiple imputations calculated using a linear regression model, taking into account demographic variables, treatment group and other scores provided at a given time point." Withdrawals due to carer time constraints, poor health of carer or relative with dementia. Specific dropouts from each group not reported.
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	Unclear risk	n/a.
Availability of training and supervision Objective outcome measures	Low risk	Trial protocol reported "each group session is led by two experienced facilitators, supported by a team, including volunteers, health and social care staff and trainees to facilitate small group discussion and activities and engage the people with dementia. All members of the RYCT team attended a training day led by one of the original RYCT programme authors."
Availability of manual or protocol for intervention All outcomes	Low risk	The group reminiscence intervention followed the RYCT programme for people with dementia and their family carers.