Table 2.

Subgroup Analysis of Efficacy and Safety Outcomes

	Efficacy outcomes
	Complete occlusion		Recurrence in DSA		Excellent functional outcome		Good functional outcome
	RR (95% CI)	P value	RR (95% CI)	P value	RR (95% CI)	P value	RR (95% CI)	P value
1. Hydrogel coil
Second generation	1.26 (1.07, 1.48)	0.005	1.09 (0.98, 1.23)	0.119	0.97 (0.90, 1.05)	0.498	0.97 (0.92, 1.03)	0.358
First generation	1.07 (0.90, 1.25)	0.450	1.04 (0.95, 1.13)	0.390	0.97 (0.88, 1.06)	0.482	0.97 (0.93, 1.00)	0.074
2. Ruptured ratio (%)
N > 30	1.21 (1.07, 1.38)	0.002	1.08 (0.99, 1.18)	0.077	1.00 (0.88, 1.12)	0.964	0.97 (0.92, 1.02)	0.187
N < 30	0.99 (0.82, 1.20)	0.938	1.02 (0.92, 1.18)	0.684	0.95 (0.88, 1.01)	0.116	0.97 (0.93, 1.01)	0.133
	Safety outcomes
	Mid-term residual neck		Retreatment		Stroke		Morbidity
	RR (95% CI)	P value	RR (95% CI)	P value	RR (95% CI)	P value	RR (95% CI)	P value
3. Hydrogel coil
Second generation	0.54 (0.34, 0.86)	0.010	0.50 (0.20, 1.21)	0.122	1.39 (0.45, 4.31)	0.570	2.31 (0.61, 8.84)	0.220
First generation	0.88 (0.56, 1.39)	0.576	1.08 (0.68, 1.69)	0.752	0.79 (0.34, 1.87)	0.594	1.03 (0.66, 1.60)	0.899
4. Ruptured ratio (%)
N > 30	0.67 (0.43, 1.03)	0.070	0.64 (0.33, 1.24)	0.186	1.39 (0.45, 4.31)	0.570	1.28 (0.79, 2.07)	0.317
N < 30	1.15 (0.33, 4.02)	0.827	1.13 (0.68, 1.88)	0.629	0.79 (0.34, 1.87)	0.594	0.73 (0.31, 1.69)	0.461