Table 3.

Subgroup Analysis.

Subgroups	No. of experiments	SMD (95% CI)	P value	Heterogeneity (p value)
Severity of SCI
Moderate	8	2.32 (1.36, 3.28)	0.001	76.98% (<0.0001)
Severe	5	2.40 (0.34, 4.45)	0.032	88.54% (<0.0001)
Cell source
BMSCs	7	2.14 (0.92, 3.36)	0.005	79.64% (0.001)
Other	6	2.54 (1.16, 3.92)	0.005	83.50% (<0.0001)
Antibiotic
Yes	9	2.57 (1.44, 3.71)	0.001	87.12% (<0.0001)
No	4	1.76 (0.92, 2.60)	0.007	0.00% (0.494)
Treatment protocol
Single dose	11	2.17 (1.30, 3.04)	<0.0001	80.07% (<0.0001)
Multi dose	2	NA	NA	NA
Delivery type
IT	6	1.68 (1.05, 2.31)	0.001	32.47% (0.205)
IP	3	3.22 (0.83, 5.61)	0.029	67.33% (0.035)
IV	2	NA	NA	NA
In situ	1	NA	NA	NA
Intraventricular	1	NA	NA	NA
Medium
DMEM	11	2.41 (1.48, 3.34)	<0.0001	82.49% (<0.0001)
Other	2	NA	NA	NA
Type of graft
Allogenic	7	2.71 (1.50, 3.92)	0.002	78.39% (<0.001)
Xenogeneic	6	1.88 (0.62, 3.14)	0.012	80.69% (0.001)
Delivery amount
≤120 μL	7	1.49 (0.81, 2.18)	0.002	56.46% (0.032)
>120 μL	6	3.32 (2.20, 4.45)	0.001	56.67% (0.012)
Follow-up duration
<8 weeks	8	2.57 (1.35, 3.79)	0.002	84.38% (<0.0001)
≥8 weeks	5	1.94 (0.74, 3.14)	0.011	67.15% (0.022)
Risk of bias
Low risk	9	2.21 (1.21, 3.20)	0.001	84.48% (<0.001)
High risk and some concern	4	2.63 (0.42, 4.85)	0.032	72.72% (0.020)

BMSCs: Bone marrow mesenchymal stem cell; DMEM: Dulbecco’s Modified Eagle’s medium; IP: Intraperitoneal; IT: Intrathecal; IV: Intravenous; NA: Not applicable due to the limited number of included studies in the subgroup