Comparison 1. Cognitive change (Alzheimer's Disease Assessment Scale ‐ cognitive subscale (ADAS‐Cog)) from baseline.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 ADAS‐Cog change from baseline	4	1110	Mean Difference (IV, Fixed, 95% CI)	‐0.26 [‐1.05, 0.52]
2 ADAS‐Cog change from baseline (using random‐effects model)	4	1110	Mean Difference (IV, Random, 95% CI)	‐0.33 [‐2.10, 1.44]
3 ADAS‐Cog change at 3 months	2	1019	Mean Difference (IV, Fixed, 95% CI)	0.14 [‐0.46, 0.74]
4 ADAS‐Cog change at 6 months	4	1067	Mean Difference (IV, Fixed, 95% CI)	‐0.08 [‐0.85, 0.70]
5 ADAS‐Cog change at 12 months	2	920	Mean Difference (IV, Fixed, 95% CI)	‐0.12 [‐1.04, 0.80]
6 ADAS‐Cog change at 18 months	2	1020	Mean Difference (IV, Fixed, 95% CI)	‐0.68 [‐1.49, 0.14]
7 ADAS‐Cog change to 18 months (last observation carried forward)	1		Mean Difference (Fixed, 95% CI)	‐1.11 [‐2.37, 0.14]
8 Modified ADAS‐Cog	1		Mean Difference (Fixed, 95% CI)	Subtotals only
8.1 Modified ADAS‐Cog change from baseline at 3 months	1	612	Mean Difference (Fixed, 95% CI)	‐0.15 [‐0.99, 0.68]
8.2 Modified ADAS‐Cog change from baseline at 6 months	1	571	Mean Difference (Fixed, 95% CI)	‐0.23 [‐1.27, 0.81]
8.3 Modified ADAS‐Cog change from baseline at 9 months	1	533	Mean Difference (Fixed, 95% CI)	‐0.66 [‐1.73, 0.41]
8.4 Modified ADAS‐Cog change from baseline at 12 months	1	514	Mean Difference (Fixed, 95% CI)	‐0.41 [‐1.76, 0.95]
8.5 Modified ADAS‐Cog change from baseline at 18 months	1	437	Mean Difference (Fixed, 95% CI)	‐0.76 [‐2.40, 0.89]
8.6 Modified ADAS‐Cog overall (0‐18) months	1	614	Mean Difference (Fixed, 95% CI)	0.41 [‐0.62, 1.44]
8.7 Modified ADAS‐Cog (last observation carried forward)	1	614	Mean Difference (Fixed, 95% CI)	‐1.04 [‐2.44, 0.37]