3. Summary of exploratory subgroup analyses: cognition.

Cognition	Effect size (SMD)	95% CI	I2	Number of studies	Number of participants	Quality of the evidence
Cognitive stimulation (CS)	0.40	0.25, 0.55	62%	34	2340	Moderate
Group CS	0.43	0.26, 0.59	56%	27	1637	Moderate
Individual CS	0.30	‐0.03, 0.64	72%	7	703	Low
20 or more group sessions	0.42	0.16, 0.67	46%	12	615	Moderate
Fewer than 20 group sessions	0.43	0.22, 0.65	61%	19	1022	Moderate
3 or more group sessions per week	0.46a	0.22, 0.69	0%	8	328	Moderate
2 or more group sessions per week	0.51b	0.34, 0.69	51%	21	1283	Moderate
1 group session per week	0.04c	‐0.17, 0.25	0%	6	354	Low
Community setting (group CS)	0.66	0.33, 0.99	77%	15	642	Moderate
Care home setting (group CS)	0.60	‐0.01, 1.20	87%	9	323	Very low
Mild dementia severity	0.71d	0.47, 0.95	43%	10	640	Moderate
Moderate dementia severity	0.21	0.03, 0.39	28%	13	778	High
Active control	0.59	0.37, 0.82	0%	5	322	Moderate
Treatment‐as‐usual	0.41	0.22, 0.60	61%	22	1315	Moderate

^a3 group sessions > 1 group session (P = 0.01).

^b2 or more > 1 group session (P = 0.0007).

^c2 group sessions > 1 group session (P = 0.003).

^dMild dementia severity > moderate dementia severity (P = 0.001).

All other subgroup comparisons shown were not statistically significant.