|
Subgroup
|
N
|
SMD (95% CI)
|
Test(s) of heterogeneity
|
Significance test(s) of SMD = 0
|
P
a
|
|---|
|
I2 (%)
|
P
|
Z
|
P
| |
|---|
|
Overall
|
16
|
0.79 (0.53–1.05)
|
74.5
|
0.000
|
5.97
|
0.000
| |
|
Four experiments excluded
|
12
|
0.75 (0.57–0.93)
|
26.5
|
0.184
|
8.19
|
0.000
| |
|
Geographic areas
| | | | | | | |
|
Asia
|
3
|
0.50 (0.15–0.85)
|
2.3
|
0.359
|
2.77
|
0.006
|
0.026
|
|
North America
|
7
|
0.81 (0.39–1.22)
|
74.2
|
0.001
|
3.80
|
0.000
|
|
Europe
|
6
|
0.92 (0.48–1.36)
|
80.8
|
0.000
|
4.08
|
0.000
|
|
Storage method
| | | | | | | |
|
Cryopreservation
|
2
|
0.20 (−0.11–0.52)
|
0.0
|
0.425
|
1.27
|
0.204
|
< 0.001
|
|
Fresh
|
14
|
0.89 (0.63–1.15)
|
69.3
|
0.000
|
6.73
|
0.000
|
|
Preparation method
| | | | | | | |
|
No preparation
|
10
|
0.82 (0.50–1.13)
|
63.1
|
0.004
|
5.14
|
0.000
|
0.023
|
|
Swim up
|
4
|
0.57 (0.20–0.94)
|
53.6
|
0.091
|
3.04
|
0.002
|
|
Discontinuous gradient
|
2
|
1.07 (−0.10–2.25)
|
95.1
|
0.000
|
1.79
|
0.074
|
|
FR cut-off value combined with AE assay method
|
|
≥ 70% vs. < 70%
|
Spectrophotometry
| | | | | | |
NC
|
| |
Spectrophotometry/BAPNA
|
1
|
0.86 (0.30–1.41)
|
–b
|
–
|
3.03
|
0.002
| |
|
≥ 50% vs. < 50%
|
Spectrophotometry
|
| |
Spectrophotometry/BAPNA
|
2
|
0.94 (0.18–1.71)
|
72.5
|
0.056
|
2.41
|
0.016
| |
|
> 50% vs. = 0%
|
Spectrophotometry
|
| |
Spectrophotometry/BAPNA
|
1
|
0.82 (0.26–1.38)
|
–
|
–
|
2.87
|
0.004
| |
|
> 0% vs. = 0%
|
Fluorometry
|
| |
PAb-acrosin
|
1
|
1.68 (1.29–2.07)
| | |
8.45
|
0.000
| |
| |
PAb-hyaluronidase
|
1
|
0.48 (0.13–0.82)
| | |
2.68
|
0.007
| |
| |
MAb 4D4-proacrosin
|
2
|
0.72 (0.32–1.13)
|
0.0
|
0.600
|
3.50
|
0.000
| |
| |
Spectrophotometry
| | | | | | | |
| |
Spectrophotometry/BAPNA
|
2
|
1.23 (−0.74–3.19)
|
93.5
|
0.000
|
1.22
|
0.221
| |
|
Accu-Sperm spectrophotometry/BAPNA
|
5
|
0.70 (0.41–0.99)
|
22.5
|
0.271
|
4.70
|
0.000
| |
|
Spectrophotometry/BAEE
|
1
|
−0.04 (−0.72–0.64)
|
–
|
–
|
0.12
|
0.908
| |
- SMD standardized mean difference, CI confidence interval, BAPNA N-α-benzoyl-dl-arginine-p-nitroanilide, BAEE N-benzoyl-l-arginine ethyl ester, NC not compared
- aComparison between subgroups with the Q test for heterogeneity
- bNot calculated
