Tadaka 2007 (VD).

Methods	RCT.
Participants	36 participants from a geriatric health services facility. Diagnosis of VD according to the DSM‐IV. Mean age: 84.25 years.
Interventions	Intervention: structured group RT. Control: treatment as usual.
Outcomes	Cognitive: MMSE. Communication: MOSES (Withdrawal subscale). Behavioural: MOSES (Irritability subscale). Mood‐related outcomes: MOSES (Depression subscale).
Length and frequency of intervention	1 × 60‐ to 90‐minute session per week for 8 weeks.
Time points measured	Prior to intervention, immediately postintervention and 6 months postintervention.
Number of participants who did not complete study	6/36 (16.67%).
Notes	Study also investigated effects of RT on 24 people with AD (Tadaka 2007 (AD)).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation list within each subset of dementia type (AD or VD).
Allocation concealment (selection bias)	Low risk	2 social workers from the facility with no connection to the study allocated participants based on the computer‐generated list.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	MMSE administered by a psychiatrist blinded to the allocation of participants at all 3 time points. MOSES completed by family members who were not blinded to group allocation.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Per protocol analysis. 3 dropouts from intervention group and 3 from control group. 1 participant from each group died while the other 4 were admitted to hospital.
Selective reporting (reporting bias)	Low risk	All outcomes listed in the methods section were reported and there was no evidence of selective outcome reporting.
Other bias	Low risk	n/a.
Availability of training and supervision Objective outcome measures	Low risk	'Specialists were trained public health nurses or clinical psychologists who had MA or PhD degrees and several years’ experience in the care of elderly people with dementia and trained in the RT group program techniques. Specialists performed roles of group leader or co‐leader to facilitate the reminsicence group program'.
Availability of manual or protocol for intervention All outcomes	Low risk	No evidence of a written protocol or manual, although a clear structure was described in the paper.