Tanaka 2021.

Study characteristics
Methods	RCT
Participants	N = 31 (18F/13M) 'Dementia' ‐ MMSE 5‐25 4/31 receiving donepezil MMSE: 15.5 (SD 5.8) Age: 86.2 (SD 7.8) Geriatric health service facility (inpatient)
Interventions	Group exercise and cognitive stimulation (N = 16) Treatment‐as‐usual (N = 15)
Outcomes	Cognition: MMSE Quality of life: QoL‐D (short version, proxy completed) Social interaction: nurses’ observation scale of geriatric patients (NOSGER) sub‐item ‘social behaviour’ Apathy scale ADL: Barthel Index Behaviour problems: Dementia Behavior Disturbance Scale
Notes	45 minutes, 2 times a week, for 8 weeks
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No detail of how randomisation was carried out
Allocation concealment (selection bias)	Unclear risk	No information as to who carried out the randomisation or whether an external person was involved
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Although observational ratings made by staff not involved in the intervention, not clear whether assessors were blinded or not
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	33% of participants in control group dropped out (compared with 6% in intervention group) ‐ unclear what effect this may have had on results
Selective reporting (reporting bias)	Low risk	Results reported for all outcomes mentioned in Methods section
Other bias ‐ training and supervision	Unclear risk	Although staff had at least 5 years experience of group interventions in this context, arrangements for specific training/supervision in the intervention used here not described
Other bias ‐ treatment manual	Unclear risk	Although the Japanese version of the CST manual was referenced, the current study appears to include additional components.