Table 2.

Subgroup analysis of the efficacy of H-CS light therapy on depressive symptoms.

Subgroup	N	Sample	MD	95% CI	P	Heterogeneity test (I2)
Age
Non-elderly (< 60 y)	4	96	−5.85	[−9.97, –1.73]	0.005	29%
Older adults (>60 y)	1	89	−0.80	[–4.56, 2.96]	-	-
Duration of intervention
Short-term (1–3 weeks)	5	215	−4.90	[−9.57, −0.23]	0.04	71%
Long-term (≥4 weeks)	2	43	−7.34	[−13.26, −1.41]	0.02	42%

H-CS, high circadian stimulus; MD, mean difference; CI, confidence interval.