Comparison 1. Cycled light (CL) versus irregular dimmed light or near darkness (ND).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Weight (g) at 4 months	1	40	Mean Difference (IV, Fixed, 95% CI)	181.0 [‐484.00, 846.00]
2 Weight (g) at 35 weeks' PMA	1	40	Mean Difference (IV, Fixed, 95% CI)	106.0 [‐41.66, 253.66]
3 Weight on day 14 (CL from 32 weeks' PMA)	1	96	Mean Difference (IV, Fixed, 95% CI)	0.0 [‐103.88, 103.88]
4 Weight gain by day 14 (CL from 32 weeks' PMA)	1	96	Mean Difference (IV, Fixed, 95% CI)	‐8.60 [‐51.37, 34.17]
5 Mean age when birth weight was regained (CL from 32 weeks' PMA)	1	96	Mean Difference (IV, Fixed, 95% CI)	0.10 [‐2.57, 2.77]
6 Cumulative mean weekly weight gain (g) (CL from birth)	1	43	Mean Difference (IV, Fixed, 95% CI)	24.0 [‐50.97, 98.97]
7 Cumulative mean weekly weight gain (g) (CL from 32 weeks' PMA)	1	40	Mean Difference (IV, Fixed, 95% CI)	29.00 [‐53.36, 111.36]
8 Daily weight gain (grams/d) during neonatal care (CL from 32 weeks' PMA)	2	128	Mean Difference (IV, Fixed, 95% CI)	2.84 [‐0.67, 6.36]
9 Calories/kg/d (CL from birth)	1	43	Mean Difference (IV, Fixed, 95% CI)	7.70 [‐18.96, 34.36]
10 Calories/kg/d (CL from 32 weeks' PMA)	1	40	Mean Difference (IV, Fixed, 95% CI)	0.20 [‐17.62, 18.02]
11 Day of life to start feeds (CL from birth)	1	43	Mean Difference (IV, Fixed, 95% CI)	2.0 [‐6.64, 10.64]
12 Day of life to start feeds (CL from 32 weeks' PMA)	1	40	Mean Difference (IV, Fixed, 95% CI)	‐1.5 [‐5.40, 2.40]
13 Day of life to full feeds (CL from birth)	1	43	Mean Difference (IV, Fixed, 95% CI)	0.80 [‐20.83, 22.43]
14 Day of life to full feeds (CL from 32 weeks' PMA)	1	40	Mean Difference (IV, Fixed, 95% CI)	‐6.70 [‐25.15, 11.75]
15 Ventilator days (CL from birth)	2	170	Mean Difference (IV, Fixed, 95% CI)	0.67 [‐2.07, 3.41]
16 Ventilator days (CL from 32 weeks' PMA)	1	40	Mean Difference (IV, Fixed, 95% CI)	‐3.00 [‐19.43, 13.43]
17 Days in supplemental oxygen (CL from birth)	1	43	Mean Difference (IV, Fixed, 95% CI)	‐16.4 [‐46.98, 14.18]
18 Days in supplemental oxygen (CL from 32 weeks' PMA)	1	40	Mean Difference (IV, Fixed, 95% CI)	‐17.6 [‐47.26, 12.06]
19 Length of stay (days) (CL from birth)	2	170	Mean Difference (IV, Fixed, 95% CI)	‐4.67 [‐14.81, 5.47]
20 Length of stay (days) (CL from 32 weeks' PMA)	2	77	Mean Difference (IV, Fixed, 95% CI)	‐12.66 [‐21.00, ‐2.33]
21 ROP (any stage) (CL from birth or from 32 weeks' PMA)	2	189	Risk Ratio (M‐H, Fixed, 95% CI)	0.83 [0.60, 1.13]
22 ROP (stage ≥ 3) (CL from birth or from 32 weeks' PMA)	2	189	Risk Ratio (M‐H, Fixed, 95% CI)	0.53 [0.25, 1.11]
23 Infants requiring laser surgery (CL from birth or from 32 weeks' PMA)	1	62	Risk Ratio (M‐H, Fixed, 95% CI)	0.51 [0.11, 2.32]
24 Ratio of day‐night activity over the 10 days preceding discharge from the hospital (CL from 32 weeks' PMA)	1	62	Mean Difference (IV, Fixed, 95% CI)	0.18 [0.17, 0.19]
25 Period length of entrained circadian rhythms over first 10 days at home (h) (CL from 32 weeks' PMA)	1	51	Mean Difference (IV, Fixed, 95% CI)	‐0.78 [‐0.89, ‐0.67]
26 Total number of movements per day (10 to 0 days before discharge) (Actogram data) (CL from 32 weeks' PMA)	1	62	Mean Difference (IV, Fixed, 95% CI)	73.0 [43.62, 102.38]
27 Total number of movements per day (1‐10 days after discharge) (Actogram data) (CL from 32 weeks' PMA)	1	51	Mean Difference (IV, Fixed, 95% CI)	82.0 [22.92, 141.08]
28 Total number of movements per day (11‐20 days after discharge) (Actogram data) (CL from 32 weeks' PMA)	1	51	Mean Difference (IV, Fixed, 95% CI)	429.0 [341.94, 516.06]
29 Total number of movements per day (21‐30 days after discharge) (Actogram data) (CL from 32 weeks' PMA)	1	29	Mean Difference (IV, Fixed, 95% CI)	536.0 [396.83, 675.17]
30 Sleep (hours/24 h) at 5 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	0.55 [‐0.37, 1.47]
31 Sleep (hours/24 h) at 11 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	‐0.09 [‐0.88, 0.70]
32 Activity count per 24 hours at 5 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	27.45 [‐2.07, 56.97]
33 Activity count per 24 hours at 11 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	5.13 [‐46.45, 56.71]
34 Wake and content (hours/24 h) at 5 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	0.89 [‐0.59, 2.37]
35 Wake and content (hours/24 h) at 11 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	1.47 [‐0.36, 3.30]
36 Crying (hours/24 h) at 5 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	‐0.47 [‐0.95, 0.01]
37 Crying (hours/24 h) at 11 weeks' CA (CL from 32 weeks' PMA)	1	37	Mean Difference (IV, Fixed, 95% CI)	‐0.57 [‐1.09, ‐0.05]