Table 6.

Meta-analysis results: SWI mean values of PD and HC were used to calculate the effect size value and confidence interval.

References	SN division	Method	PD			HC			Hedge's g	SE	Confidence interval
			N	Mean	SD	N	Mean	SD			Low	High
Gupta et al. (45)	Global	SWI hypointensity	11	0.36	0.81	11	0.64	0.67	0.36	0.43	−0.48	1.21
Zhang et al. (49)	Ipsilateral	Phase values	40	0.13	0.05	26	0.12	0.04	0.21	0.25	−0.28	0.71
	Contralateral***			0.16	0.05		0.12	0.04	0.85	0.26	0.34	1.37
Jin et al. (50)	Global***	Phase values	87	−0.18	0.03	50	−0.16	0.03	0.66	0.18	0.31	1.02
Lotfipour et al. (51)	SN	Relative susceptibility	9	0.05	0.01	11	0.04	0.01	0.96	0.48	0.02	1.89
	SNc*			0.06	0.01		0.04	0.01	1.92	0.55	0.84	2.99
Wang et al. (46)	Global*	Phase values	16	−0.23	0.05	44	−0.17	0.07	0.91	0.30	0.31	1.50
Rossi et al. (23)	Lateral SNc	SWI contrast	36	7.20	3.50	21	9.10	5.20	0.45	0.28	−0.10	0.99
	Medial SNc*			5.70	5.90		9.90	6.50	0.68	0.28	0.12	1.23
Wang et al. (47)	SNc**	Phase values	20	0.03	0.03	14	0.08	0.02	1.85	0.42	1.03	2.67
	SNr**			−0.55	0.18		−0.37	0.17	1.00	0.37	0.27	1.72
Wu et al. (48)	Global*	Phase values	54	−0.13	0.01	40	−0.10	0.02	1.97	0.25	1.48	2.47
Isaias et al. (12)	Ipsilateral	Phase values	18	0.16	0.05	18	0.13	0.03	0.71	0.34	0.04	1.39
	Contralateral			0.15	0.05		0.13	0.03	0.47	0.34	−0.19	1.14
Martin-Bastida et al. (52)	Global**	Phase values	70	0.11	0.02	20	0.04	0.02	3.47	0.36	2.76	4.18

All SN subdivisions were included.

^***Significantly different from controls (p < 0.001).

^**Significantly different from controls (p < 0.01).

^*Significantly different from controls (p < 0.05).