Comparison 1. Bright light versus control.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Cognition following 10‐42 days of treatment	3	156	Mean Difference (IV, Fixed, 95% CI)	1.24 [‐0.81, 3.28]
2 Sleep onset latency following 2‐6 weeks of treatment	2	107	Mean Difference (IV, Fixed, 95% CI)	‐2.27 [‐14.20, 9.65]
3 Total sleep duration following 10 days to 10 weeks of treatment	6	321	Mean Difference (IV, Random, 95% CI)	‐1.07 [‐35.47, 33.33]
4 Total sleep duration following 6 months of treatment	2	128	Mean Difference (IV, Random, 95% CI)	‐7.78 [‐69.01, 53.44]
5 Sleep efficiency following 2‐10 weeks of treatment	3	157	Mean Difference (IV, Random, 95% CI)	3.25 [‐0.53, 7.04]
6 Number of night‐time awakenings following 2‐10 weeks of treatment	3	172	Mean Difference (IV, Random, 95% CI)	‐1.55 [‐5.43, 2.33]
7 Agitation following 10 days to 10 weeks of treatment	4	250	Std. Mean Difference (IV, Random, 95% CI)	‐0.01 [‐0.31, 0.29]
8 Psychiatric symptoms following 6 to 10 weeks of treatment	2	157	Mean Difference (IV, Random, 95% CI)	2.22 [‐6.48, 10.91]
9 Depression following 2 to 10 weeks of treatment	3	161	Std. Mean Difference (IV, Random, 95% CI)	0.09 [‐0.54, 0.73]