Six studies were included (8,953 participants at most: in one study it was unclear if the numbers were reported more than once); total exposure (game and practice) was 573,896. There was one RCT (n=140), two prospective cohort studies (n=2,534), one case-control study (n=276) and two controlled cohort studies (n=6,003).
Methodological flaws in the studies included lack of statistical power, lack of randomisation, lack of reporting of compliance and inadequate description of ACL injury status.
The authors stated that three of the six studies found that neuromuscular training interventions significantly reduced the likelihood of ACL injury in female athletes, but the forest plot indicated that only one study reported a significantly reduced risk of ACL with the intervention compared with control. When estimates were pooled, neuromuscular training interventions were associated with a significant reduction in the risk of ACL injuries (OR 0.40, 95% CI: 0.26, 0.61).
Compliance rates ranged from 28 to 100% (based on five studies).
Components of effective interventions: all four studies that included plyometrics reported a reduced risk of ACL; three of these studies combined pylometrics with analysis of movement and feedback.