Comparison 1. Cognitive training vs control immediately post intervention.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Change in a global measure of cognition (composite)	26	1389	Std. Mean Difference (Random, 95% CI)	0.42 [0.23, 0.61]
2 Change in a global measure of cognition (composite)_zero correlation	26	1389	Std. Mean Difference (Random, 95% CI)	0.24 [0.12, 0.36]
3 Change in a global measure of cognition	20	1288	Std. Mean Difference (IV, Random, 95% CI)	0.65 [0.26, 1.05]
4 Change in a global measure of cognition_zero correlation	20	1287	Std. Mean Difference (IV, Random, 95% CI)	0.27 [0.04, 0.50]
5 Change in disease progression	5	215	Std. Mean Difference (IV, Random, 95% CI)	1.07 [0.59, 1.55]
6 Change in delayed memory	11	543	Std. Mean Difference (IV, Random, 95% CI)	0.81 [0.29, 1.32]
7 Change in immediate memory	17	762	Std. Mean Difference (IV, Random, 95% CI)	0.74 [0.37, 1.12]
8 Change in attention and working memory	12	551	Std. Mean Difference (IV, Random, 95% CI)	0.56 [0.08, 1.05]
9 Change in language (naming)	5	311	Std. Mean Difference (IV, Random, 95% CI)	0.62 [0.11, 1.12]
10 Change in verbal letter fluency	12	544	Std. Mean Difference (IV, Random, 95% CI)	0.22 [‐0.07, 0.50]
11 Change in verbal category fluency	9	475	Std. Mean Difference (IV, Random, 95% CI)	0.52 [0.23, 0.81]
12 Change in executive function	11	511	Std. Mean Difference (IV, Random, 95% CI)	0.75 [0.28, 1.22]
13 Change in speed of information processing	6	201	Std. Mean Difference (IV, Random, 95% CI)	0.22 [‐0.11, 0.54]
14 Change in meta cognition (self‐reported)	2	41	Std. Mean Difference (IV, Random, 95% CI)	0.50 [‐0.15, 1.14]
15 Change in meta cognition (informant‐reported)	2	56	Std. Mean Difference (IV, Random, 95% CI)	‐0.01 [‐1.29, 1.26]
16 Change in participants' mood	8	577	Std. Mean Difference (IV, Random, 95% CI)	0.72 [‐0.10, 1.54]
17 Change in capacity for activities of daily living	10	687	Std. Mean Difference (IV, Random, 95% CI)	0.12 [‐0.11, 0.35]
18 Change in general health and quality of life	5	630	Std. Mean Difference (IV, Random, 95% CI)	‐0.04 [‐0.38, 0.29]
19 Change in behavioural and psychological symptoms of dementia (BPSD)	6	493	Std. Mean Difference (IV, Random, 95% CI)	0.44 [‐0.34, 1.22]
20 Participant burden (retention rates)	17	1282	Odds Ratio (M‐H, Random, 95% CI)	0.73 [0.37, 1.43]
21 Change in burden of care (CAREGIVER)	2	405	Std. Mean Difference (IV, Random, 95% CI)	‐0.11 [‐0.36, 0.15]
22 Change in quality of life (CAREGIVER)	1	36	Std. Mean Difference (IV, Random, 95% CI)	0.16 [‐0.50, 0.83]
23 Change in mood and well‐being (CAREGIVER)	1	36	Std. Mean Difference (IV, Random, 95% CI)	0.98 [0.27, 1.68]