Table 5.
Summary of Rs values for AE assay
| Subgroup | N | Rs (95% CI) | Test(s) of heterogeneity | Significance test(s) of Rs = 0 | P a | ||
|---|---|---|---|---|---|---|---|
| I2 (%) | P | Z | P | ||||
| Overall | 13 | 0.39 (0.18–0.60) | 95.7 | 0.000 | 3.70 | 0.000 | |
| Two experiments excluded | 11 | 0.38 (0.27–0.48) | 67.1 | 0.001 | 7.19 | 0.000 | |
| Geographic area | |||||||
| Asia | 4 | 0.24 (0.05–0.42) | 66.7 | 0.029 | 2.49 | 0.013 | < 0.001 |
| North America | 1 | 0.54 (0.43–0.65) | –b | – | 9.70 | 0.000 | |
| Europe | 6 | 0.46 (0.37–0.54) | 0.0 | 0.798 | 11.02 | 0.000 | |
| Preparation method | |||||||
| No preparation | 6 | 0.42 (0.30–0.55) | 63.4 | 0.018 | 6.72 | 0.000 | 0.04 |
| Swim up | 3 | 0.27 (0.01–0.53) | 80.6 | 0.006 | 2.01 | 0.044 | |
| Discontinuous gradient | 2 | 0.42 (0.23–0.60) | 0.0 | 0.893 | 4.41 | 0.000 | |
| AE assay method | |||||||
| Fluorometry | |||||||
| MAb 4D4-proacrosin | 1 | 0.49 (0.27–0.70) | – | – | 4.43 | 0.000 | < 0.001 |
| Spectrophotometry | |||||||
| Spectrophotometry/BAPNA | 5 | 0.44 (0.35–0.54) | 0.0 | 0.618 | 9.08 | 0.000 | |
| Accu-Sperm spectrophotometry/BAPNA | 2 | 0.09 (−0.05–0.23) | 0.0 | 0.352 | 1.22 | 0.223 | |
| Substrate assay | |||||||
| Acrosin target with gelatine substrate assay | 2 | 0.43 (0.30–0.56) | 0.0 | 0.997 | 6.51 | 0.000 | |
| Hyaluronidase target with agar/hyaluronic acid mixture substrate assay | 1 | 0.54 (0.43–0.65) | – | – | 9.70 | 0.000 | |
Rs spearman correlation coefficient, CI confidence interval, BAPNA N-α-benzoyl-dl-arginine-p-nitroanilide
aComparison between subgroups with the Q test for heterogeneity
bNot calculated