Table 4. Comparison of ACL-Injured vs. Controls: Females Only.
| Comparison* | Sample (knee) | Mean difference (95% CI) | Significance Z (p-value) | Remark | |
|---|---|---|---|---|---|
| Female ACL-injured vs. controls (all studies)22-24,36,37) | 470 (228 vs. 242) | –0.38 (–0.59 to –0.18) | Z = 3.67 (p = 0.0002) | ACL-injured females had smaller notch volumes irrespective of nature of injury or injured/healthy knee used for measurement. | |
| Q = 7.26, df = 4 (p = 0.12), I2 = 45%, τ2 = 0.02 | |||||
| Females: non-contact injury (2 studies)23,36) | 262 (131 vs. 131) | –0.54 (–0.78 to –0.31) | Z = 4.51 (p < 0.00001) | Subgroup difference Q = 1.98, df = 1 (p = 0.16), I2 = 49.5% | Effect size increases in non-contact injury group. No significant difference between subgroups based on mechanism of injury |
| Females: unrestricted (3 studies)22,24,37) | 208 (97 vs. 111) | –0.29 (–0.55 to –0.02) | Z = 2.10 (p = 0.04) | ||
| Q = 3.67, df = 2 (p = 0.16), I2 = 45%, τ2 = 0.03 | |||||
| Females: injured knees (4 studies)22-24,37) | 348 (167 vs. 181) | –0.38 (–0.64 to –0.13) | Z = 2.92 (p = 0.003) | Subgroup difference Q = 0.00, df = 1 (p = 1.00), I2 = 0% | No significant difference between subgroups based whether injured or healthy contralateral knee was used |
| Females: healthy contralateral knee (1 study)36) | 122 (61 vs. 61) | –0.38 (–0.78 to 0.02) | Z = 1.87 (p = 0.06) | ||
| NA | |||||
ACL: anterior cruciate ligament, CI: confidence interval, Q: Cochrane's Q statistic (χ2), df: degrees of freedom, τ2: tau2, NA: not available.
*All analyses used inverse-variance weighted random effects model. Unit of Effect measure: mean difference in cm3.
Statistically significant, p < 0.05.